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Utility Tool — GST Invoice Generator

GST Invoice Generator — Create and Print GST Tax Invoices Free

Generate GST-compliant tax invoices with all mandatory fields — GSTIN, HSN, CGST/SGST breakdown, and taxable value. Print or save as PDF instantly.

Generate & Download Invoice

Formula & How It Works

Taxable Value = Qty × Rate
CGST = Taxable Value × (GST Rate ÷ 2) ÷ 100
SGST = Taxable Value × (GST Rate ÷ 2) ÷ 100
Invoice Total = Taxable Value + CGST + SGST

Worked Example

Seller: ABC Traders | Buyer: XYZ Pvt Ltd | Product: Office Chair × 5 @ ₹8,000 | GST 18%

Taxable = ₹40,000 | CGST ₹3,600 | SGST ₹3,600 | Total = ₹47,200

When to Use This Calculator

  • Create quick invoices for one-off sales
  • Generate sample invoice format for new business
  • Create pro-forma invoice for customer approval
  • Print backup invoice when billing software is down
  • Use as reference for setting up ERP billing

Frequently Asked Questions

Supplier name, GSTIN, address; Recipient name, GSTIN (for B2B); Invoice number, date; HSN/SAC code; Taxable value; GST rate and amount (CGST+SGST or IGST); Total value.
For goods: on or before date of removal. For services: within 30 days of supply. For banking/insurance: within 45 days.
Tax invoice is for taxable supplies (you charge GST). Bill of supply is for exempt/nil-rated supplies or composition dealers (no GST charged).
Yes. Digital invoices are valid under GST as long as they contain all mandatory fields and are issued in a tamper-proof format.

Related Tools — Utility Tools

GST Calculator Invoice Number Generator Taxable Value Calculator HSN Code Finder

Browse all free tools at /free-tools/

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'); w.document.close(); w.focus(); setTimeout(function () { w.print(); }, 400); } function resetCalc() { ['igSellerName', 'igSellerGST', 'igSellerPAN', 'igSellerContact', 'igSellerAddr', 'igBuyerName', 'igBuyerGST', 'igBuyerMobile', 'igBuyerEmail', 'igBuyerAddr', 'igShipAddr', 'igInvNo', 'igDueDate', 'igPO', 'igEWay', 'igPayTerms', 'igUPI', 'igBank', 'igVehicle', 'igNotes', 'igTerms' ].forEach(function (id) { var el = document.getElementById(id); if (el) el.value = ''; }); document.getElementById('igItemsWrapper').innerHTML = ''; itemCount = 0; addItem(); document.getElementById('resultBox').classList.remove('show'); } // ── Global state ──────────────────────────────────────────────────────────── var CSYM = { INR: '\u20b9', USD: '$', AED: 'AED\u00a0', GBP: '\u00a3', EUR: '\u20ac', SAR: 'SAR\u00a0', ZAR: 'R\u00a0', AUD: 'A$' }; var gCurr = '\u20b9'; // current currency symbol — shared across ALL functions var gTmpl = 'classic'; // current template function setCurrency() { var sel = document.getElementById('igCurrency'); gCurr = sel ? (CSYM[sel.value] || '\u20b9') : '\u20b9'; // Update live row displays document.querySelectorAll('[id^="item-"]').forEach(function (el) { var id = el.id.split('-')[1]; calcRow(id); }); } function setTmpl(name, btn) { gTmpl = name; document.querySelectorAll('.tmpl-btn').forEach(function (b) { b.classList.remove('active'); }); if (btn) btn.classList.add('active'); } // ── Override calcRow to use gCurr ─────────────────────────────────────────── function calcRow(id) { var qty = parseFloat(document.getElementById('qty-' + id).value) || 0; var rate = parseFloat(document.getElementById('rate-' + id).value) || 0; var disc = parseFloat(document.getElementById('disc-' + id).value) || 0; var gstR = parseFloat(document.getElementById('gst-' + id).value) || 0; var incl = document.getElementById('incl-' + id).value; var gross = qty * rate; var dAmt = gross * disc / 100; var after = gross - dAmt; var taxable, taxAmt; if (incl === 'incl') { taxable = after / (1 + gstR / 100); taxAmt = after - taxable; } else { taxable = after; taxAmt = taxable * gstR / 100; } var total = taxable + taxAmt; document.getElementById('taxable-' + id).textContent = gCurr + fmt(taxable); document.getElementById('taxamt-' + id).textContent = gCurr + fmt(taxAmt); document.getElementById('discamt-' + id).textContent = gCurr + fmt(dAmt); document.getElementById('total-' + id).textContent = gCurr + fmt(total); updateGrandTotal(); } // ── Upload helpers ─────────────────────────────────────────────────────────── function prevImg(input, imgId, previewId, zcId) { var file = input.files[0]; if (!file) return; var r = new FileReader(); r.onload = function (e) { document.getElementById(imgId).src = e.target.result; document.getElementById(previewId).style.display = 'flex'; var zc = document.getElementById(zcId); if (zc) zc.style.display = 'none'; }; r.readAsDataURL(file); } function rmImg(imgId, previewId, zcId) { document.getElementById(imgId).src = ''; document.getElementById(previewId).style.display = 'none'; var zc = document.getElementById(zcId); if (zc) zc.style.display = 'flex'; } function uzDrag(e, zoneId) { e.preventDefault(); document.getElementById(zoneId).classList.add('dragover'); } function uzLeave(zoneId) { document.getElementById(zoneId).classList.remove('dragover'); } function uzDrop(e, imgId, previewId, zcId) { e.preventDefault(); var zoneId = (imgId === 'logoImg') ? 'logoZone' : 'sigZone'; document.getElementById(zoneId).classList.remove('dragover'); var file = e.dataTransfer.files[0]; if (!file || !file.type.startsWith('image/')) return; var r = new FileReader(); r.onload = function (ev) { document.getElementById(imgId).src = ev.target.result; document.getElementById(previewId).style.display = 'flex'; var zc = document.getElementById(zcId); if (zc) zc.style.display = 'none'; }; r.readAsDataURL(file); } // ── UPI QR preview ─────────────────────────────────────────────────────────── function previewUpiQr() { var upi = document.getElementById('igUPI').value.trim(); var wrap = document.getElementById('upiQRWrap'); var div = document.getElementById('upiQRDiv'); if (!upi) { wrap.classList.remove('show'); return; } wrap.classList.add('show'); div.innerHTML = ''; if (typeof QRCode !== 'undefined') { try { new QRCode(div, { text: 'upi://pay?pa=' + encodeURIComponent(upi) + '&pn=VasyERP', width: 80, height: 80, colorDark: '#303335', colorLight: '#ffffff', correctLevel: QRCode.CorrectLevel.M }); } catch (e) { } } } // ── Copy billing ───────────────────────────────────────────────────────────── function copyBilling() { document.getElementById('igShipAddr').value = document.getElementById('igBuyerAddr').value; } // ── Duplicate row ──────────────────────────────────────────────────────────── function dupRow(srcId) { addItem(); var newId = itemCount; ['name', 'sku', 'sdesc', 'hsn', 'qty', 'unit', 'rate', 'disc', 'gst', 'incl'].forEach(function (f) { var s = document.getElementById(f + '-' + srcId); var d = document.getElementById(f + '-' + newId); if (s && d) d.value = s.value; }); calcRow(newId); } // ── Amount in words ─────────────────────────────────────────────────────────── function numWords(n) { n = Math.round(n); if (n === 0) return 'Zero'; var a = ['', 'One', 'Two', 'Three', 'Four', 'Five', 'Six', 'Seven', 'Eight', 'Nine', 'Ten', 'Eleven', 'Twelve', 'Thirteen', 'Fourteen', 'Fifteen', 'Sixteen', 'Seventeen', 'Eighteen', 'Nineteen']; var b = ['', '', 'Twenty', 'Thirty', 'Forty', 'Fifty', 'Sixty', 'Seventy', 'Eighty', 'Ninety']; function w(x) { if (x < 20) return a[x]; if (x < 100) return b[Math.floor(x / 10)] + (x % 10 ? ' ' + a[x % 10] : ''); if (x < 1000) return a[Math.floor(x / 100)] + ' Hundred' + (x % 100 ? ' ' + w(x % 100) : ''); if (x < 100000) return w(Math.floor(x / 1000)) + ' Thousand' + (x % 1000 ? ' ' + w(x % 1000) : ''); if (x < 10000000) return w(Math.floor(x / 100000)) + ' Lakh' + (x % 100000 ? ' ' + w(x % 100000) : ''); return w(Math.floor(x / 10000000)) + ' Crore' + (x % 10000000 ? ' ' + w(x % 10000000) : ''); } return w(n) + ' Only'; } // ── Invoice History ─────────────────────────────────────────────────────────── function saveHist(invNo, customer, total, data) { var h = JSON.parse(localStorage.getItem('vasy_inv') || '[]'); h.unshift({ id: Date.now(), invNo: invNo, customer: customer, total: total, date: new Date().toLocaleDateString('en-IN'), curr: gCurr, data: data }); if (h.length > 20) h = h.slice(0, 20); localStorage.setItem('vasy_inv', JSON.stringify(h)); renderHist(); } function renderHist() { var h = JSON.parse(localStorage.getItem('vasy_inv') || '[]'); var body = document.getElementById('histBody'); if (!body) return; if (!h.length) { body.innerHTML = '
No invoices yet.
'; return; } body.innerHTML = h.map(function (e) { var cs = e.curr || '\u20b9'; return '
' + '
' + e.customer + '
' + '
' + e.invNo + ' · ' + e.date + '
' + '
' + cs + parseFloat(e.total).toLocaleString('en-IN', { minimumFractionDigits: 2, maximumFractionDigits: 2 }) + '
' + '
' + '' + '' + '' + '
'; }).join(''); } function clearHist() { if (!confirm('Clear all saved invoices?')) return; localStorage.removeItem('vasy_inv'); renderHist(); } function delHist(id) { var h = JSON.parse(localStorage.getItem('vasy_inv') || '[]'); localStorage.setItem('vasy_inv', JSON.stringify(h.filter(function (e) { return e.id !== id; }))); renderHist(); } function reopenHist(id) { var h = JSON.parse(localStorage.getItem('vasy_inv') || '[]'); var entry = h.find(function (e) { return e.id === id; }); if (!entry || !entry.data) return; loadForm(entry.data); window.scrollTo({ top: document.getElementById('calculator').offsetTop - 80, behavior: 'smooth' }); } function dupHist(id) { reopenHist(id); setTimeout(function () { var el = document.getElementById('igInvNo'); if (el && el.value) { var p = el.value.split('/'); p[p.length - 1] = String((parseInt(p[p.length - 1]) || 0) + 1).padStart(4, '0'); el.value = p.join('/'); } }, 120); } function captureForm() { var data = {}; ['igSellerName', 'igSellerGST', 'igSellerPAN', 'igSellerContact', 'igSellerAddr', 'igBuyerName', 'igBuyerGST', 'igBuyerMobile', 'igBuyerEmail', 'igBuyerAddr', 'igShipAddr', 'igInvNo', 'igDate', 'igDueDate', 'igPO', 'igEWay', 'igGSTType', 'igRC', 'igPS', 'igPayTerms', 'igUPI', 'igBank', 'igVehicle', 'igNotes', 'igTerms', 'igCurrency'].forEach(function (id) { var el = document.getElementById(id); if (el) data[id] = el.value; }); data.items = []; document.querySelectorAll('[id^="item-"]').forEach(function (el) { var id = el.id.split('-')[1]; var item = {}; ['name', 'sku', 'sdesc', 'hsn', 'qty', 'unit', 'rate', 'disc', 'gst', 'incl'].forEach(function (f) { var fe = document.getElementById(f + '-' + id); if (fe) item[f] = fe.value; }); data.items.push(item); }); return data; } function loadForm(data) { resetCalc(); ['igSellerName', 'igSellerGST', 'igSellerPAN', 'igSellerContact', 'igSellerAddr', 'igBuyerName', 'igBuyerGST', 'igBuyerMobile', 'igBuyerEmail', 'igBuyerAddr', 'igShipAddr', 'igInvNo', 'igDate', 'igDueDate', 'igPO', 'igEWay', 'igGSTType', 'igRC', 'igPS', 'igPayTerms', 'igUPI', 'igBank', 'igVehicle', 'igNotes', 'igTerms', 'igCurrency'].forEach(function (id) { var el = document.getElementById(id); if (el && data[id] !== undefined) el.value = data[id]; }); if (data.igCurrency) setCurrency(); document.getElementById('igItemsWrapper').innerHTML = ''; itemCount = 0; if (data.items && data.items.length) { data.items.forEach(function (item) { addItem(); var id = itemCount; ['name', 'sku', 'sdesc', 'hsn', 'qty', 'unit', 'rate', 'disc', 'gst', 'incl'].forEach(function (f) { var fe = document.getElementById(f + '-' + id); if (fe && item[f] !== undefined) fe.value = item[f]; }); calcRow(id); }); } else { addItem(); } } // ── Share ───────────────────────────────────────────────────────────────────── // Build the print-ready HTML string (same CSS used in openPrintWindow) function buildInvoiceDocStr() { var previewEl = document.getElementById('igPreview'); if (!previewEl || !previewEl.innerHTML.trim()) return null; var content = previewEl.innerHTML; return ( '' + 'Invoice - VasyERP' + '' + content + ' ' ); } function shaWA() { var previewEl = document.getElementById('igPreview'); if (!previewEl || !previewEl.innerHTML.trim()) { toast('Please generate an invoice first'); return; } var seller = document.getElementById('igSellerName').value || 'VasyERP'; var buyer = document.getElementById('igBuyerName').value || ''; var invNo = document.getElementById('igInvNo').value || ''; var buyerMobile = document.getElementById('igBuyerMobile').value || ''; var waMsg = (buyer ? 'Dear ' + buyer + ',' : 'Hi,') + '\n\nPlease find your invoice' + (invNo ? ' #' + invNo : '') + ' from ' + seller + ' attached.' + '\n\nGenerated using VasyERP Free Invoice Generator.' + '\nhttps://vasyerp.com'; // ── Try Web Share API with PDF file (works on Android & iOS Chrome/Safari) ── if (navigator.share && navigator.canShare) { var docStr = buildInvoiceDocStr(); if (docStr) { // Convert HTML to a Blob, then use html2canvas isn't available — // so we share as an HTML file that renders as invoice // Best available: share the HTML as a file, which WhatsApp shows as attachment var blob = new Blob([docStr], { type: 'text/html;charset=utf-8' }); var file = new File([blob], 'Invoice-' + (invNo || 'VasyERP') + '.html', { type: 'text/html' }); // Check if sharing files is supported if (navigator.canShare({ files: [file] })) { navigator.share({ title: 'Invoice ' + (invNo ? '#' + invNo + ' ' : '') + 'from ' + seller, text: waMsg, files: [file] }).then(function () { toast('Invoice shared successfully'); }).catch(function (err) { if (err.name !== 'AbortError') { // User didn't cancel — fallback to text share shaWATextFallback(waMsg, buyerMobile); } }); return; } } // Web Share API available but no file support — share text + link navigator.share({ title: 'Invoice from ' + seller, text: waMsg }).then(function () { toast('Shared successfully'); }).catch(function (err) { if (err.name !== 'AbortError') shaWATextFallback(waMsg, buyerMobile); }); return; } // ── Desktop fallback: download PDF + open WhatsApp with message ── shaWADesktopFallback(waMsg, buyerMobile, seller, invNo); } function shaWATextFallback(msg, mobile) { // Open WhatsApp with pre-filled text (no attachment) var url = mobile ? 'https://wa.me/91' + mobile.replace(/\D/g, '') + '?text=' + encodeURIComponent(msg) : 'https://wa.me/?text=' + encodeURIComponent(msg); window.open(url, '_blank'); } function shaWADesktopFallback(msg, mobile, seller, invNo) { // Step 1: auto-download the invoice as HTML file var docStr = buildInvoiceDocStr(); if (docStr) { try { var blob = new Blob([docStr], { type: 'text/html;charset=utf-8' }); var a = document.createElement('a'); a.href = URL.createObjectURL(blob); a.download = 'Invoice-' + (invNo || seller || 'VasyERP') + '.html'; document.body.appendChild(a); a.click(); document.body.removeChild(a); setTimeout(function () { URL.revokeObjectURL(a.href); }, 5000); } catch (e) { } } // Step 2: open WhatsApp with the text message // User can then manually attach the downloaded file var url = mobile ? 'https://wa.me/91' + mobile.replace(/\D/g, '') + '?text=' + encodeURIComponent(msg) : 'https://wa.me/?text=' + encodeURIComponent(msg); toast('Invoice downloaded — attach it in WhatsApp'); setTimeout(function () { window.open(url, '_blank'); }, 800); } function shaEmail() { var seller = document.getElementById('igSellerName').value || 'VasyERP'; var buyer = document.getElementById('igBuyerName').value || 'Customer'; var invNo = document.getElementById('igInvNo').value || ''; var email = document.getElementById('igBuyerEmail').value || ''; var subject = 'Invoice' + (invNo ? ' ' + invNo : '') + ' from ' + seller; var body = 'Dear ' + buyer + ',\n\nPlease find your invoice' + (invNo ? ' #' + invNo : '') + ' enclosed.\n\nGenerated using VasyERP Free Invoice Generator.\nhttps://vasyerp.com\n\nRegards,\n' + seller; window.location.href = 'mailto:' + email + '?subject=' + encodeURIComponent(subject) + '&body=' + encodeURIComponent(body); } function shaLink() { var url = window.location.href.split('?')[0] + '?utm_source=share&utm_medium=tool_share&utm_campaign=gst-invoice-generator'; navigator.clipboard.writeText(url).then(function () { toast('Link copied!'); }).catch(function () { toast('URL: ' + url); }); } function dlPDF() { printInvoice(); toast('Print dialog open \u2014 select Save as PDF'); } function toast(msg) { var t = document.getElementById('p27toast'); if (!t) return; t.textContent = msg; t.classList.add('show'); setTimeout(function () { t.classList.remove('show'); }, 2600); } // ── MAIN CALCULATE ──────────────────────────────────────────────────────────── function calculate() { setCurrency(); // ensure gCurr is fresh var items = getItems(); if (!items.length) { alert('Add at least one line item.'); return; } var seller = document.getElementById('igSellerName').value || 'Your Business'; var sellerG = document.getElementById('igSellerGST').value || ''; var sellerP = document.getElementById('igSellerPAN').value || ''; var sellerC = document.getElementById('igSellerContact').value || ''; var sellerA = document.getElementById('igSellerAddr').value || ''; var buyer = document.getElementById('igBuyerName').value || 'Customer'; var buyerG = document.getElementById('igBuyerGST').value || ''; var buyerM = document.getElementById('igBuyerMobile').value || ''; var buyerE = document.getElementById('igBuyerEmail').value || ''; var buyerA = document.getElementById('igBuyerAddr').value || ''; var shipA = document.getElementById('igShipAddr').value || buyerA; var invNo = document.getElementById('igInvNo').value || 'INV/25-26/0001'; var date = document.getElementById('igDate').value || new Date().toISOString().split('T')[0]; var dueD = document.getElementById('igDueDate').value || ''; var po = document.getElementById('igPO').value || ''; var eway = document.getElementById('igEWay').value || ''; var gstType = document.getElementById('igGSTType').value; var rcEl = document.getElementById('igRC'); var rc = rcEl ? rcEl.value : 'no'; var psEl = document.getElementById('igPS'); var ps = psEl ? psEl.value : ''; var payT = document.getElementById('igPayTerms').value || ''; var upi = document.getElementById('igUPI').value || ''; var bank = document.getElementById('igBank').value || ''; var veh = document.getElementById('igVehicle').value || ''; var notes = document.getElementById('igNotes').value || ''; var terms = document.getElementById('igTerms').value || 'Goods once sold will not be taken back.'; var logoSrc = document.getElementById('logoImg').src; var sigSrc = document.getElementById('sigImg').src; var cs = gCurr; // use global currency symbol var subTotal = 0, totDisc = 0, totTax = 0, grand = 0; items.forEach(function (it) { subTotal += it.taxable; totDisc += it.discAmt; totTax += it.taxAmt; grand += it.total; }); var roundOff = Math.round(grand) - grand; var final = grand + roundOff; // ── Table styles based on template ── var td = 'padding:5px 6px;border:1px solid #dde4ea;font-size:10.5px;word-break:break-word;overflow-wrap:break-word;'; var thBg = '#f0f8ff', thColor = '#303335'; if (gTmpl === 'modern') { thBg = '#3BACDE'; thColor = '#fff'; } else if (gTmpl === 'corporate') { thBg = '#303335'; thColor = '#fff'; } else if (gTmpl === 'retail') { thBg = '#E4F1F6'; thColor = '#303335'; } else if (gTmpl === 'manufacturing') { thBg = '#f0f0f0'; thColor = '#303335'; } var th = 'padding:5px 6px;border:1px solid #dde4ea;font-size:10.5px;font-weight:700;word-break:break-word;background:' + thBg + ';color:' + thColor + ';'; // ── Header style based on template ── var hStyle, tStyle, sStyle, infoColor = '#666'; if (gTmpl === 'modern') { hStyle = 'background:linear-gradient(135deg,#303335 0%,#1a1d1f 100%);color:#fff;padding:22px;border-radius:10px 10px 0 0;margin:-24px -24px 18px;display:flex;justify-content:space-between;align-items:flex-start'; tStyle = 'font-size:22px;font-weight:800;letter-spacing:1px;color:#3BACDE;margin-bottom:4px'; sStyle = 'font-size:15px;font-weight:700;color:#fff'; infoColor = 'rgba(255,255,255,.75)'; } else if (gTmpl === 'corporate') { hStyle = 'border-left:5px solid #303335;padding-left:18px;margin-bottom:16px;display:flex;justify-content:space-between;align-items:flex-start'; tStyle = 'font-size:18px;font-weight:800;color:#303335;text-transform:uppercase;letter-spacing:2px;margin-bottom:4px'; sStyle = 'font-size:15px;font-weight:700;color:#303335'; } else if (gTmpl === 'retail') { hStyle = 'background:#E4F1F6;padding:16px;border-radius:10px;margin-bottom:14px;display:flex;justify-content:space-between;align-items:flex-start'; tStyle = 'font-size:16px;font-weight:800;color:#3BACDE;text-transform:uppercase;letter-spacing:1px;margin-bottom:4px'; sStyle = 'font-size:15px;font-weight:700;color:#303335'; } else if (gTmpl === 'manufacturing') { hStyle = 'border:2px solid #303335;padding:14px;border-radius:8px;margin-bottom:14px;display:flex;justify-content:space-between;align-items:flex-start'; tStyle = 'font-size:20px;font-weight:800;color:#303335;margin-bottom:4px'; sStyle = 'font-size:15px;font-weight:700;color:#303335'; } else { // classic hStyle = 'display:flex;justify-content:space-between;align-items:flex-start;border-bottom:2.5px solid #3BACDE;padding-bottom:14px;margin-bottom:14px'; tStyle = 'font-size:20px;font-weight:800;color:#303335;letter-spacing:-.5px'; sStyle = 'font-size:16px;font-weight:700;color:#3BACDE;margin-top:3px'; } var logoHtml = (logoSrc && logoSrc.length > 10) ? 'Logo' : ''; var sigHtml = (sigSrc && sigSrc.length > 10) ? 'Sig' : ''; // ── Build rows ── var rows = ''; items.forEach(function (it, i) { var cgst = gstType === 'cgst_sgst' ? it.taxAmt / 2 : 0; var sgst = gstType === 'cgst_sgst' ? it.taxAmt / 2 : 0; var igst = gstType === 'igst' ? it.taxAmt : 0; rows += '' + '' + (i + 1) + '' + '' + it.name + '' + '' + (it.sku || '—') + '' + '' + (it.sdesc || '—') + '' + '' + it.hsn + '' + '' + it.qty + '' + '' + it.unit + '' + '' + cs + fmt(it.rate) + '' + '' + (it.disc > 0 ? it.disc + '%' : '—') + '' + '' + cs + fmt(it.taxable) + '' + '' + it.gstRate + '%' + (gstType === 'cgst_sgst' ? '' + cs + fmt(cgst) + '' + cs + fmt(sgst) + '' : '' + cs + fmt(igst) + '') + '' + cs + fmt(it.total) + '' + ''; }); var taxCols = gstType === 'cgst_sgst' ? 'CGSTSGST' : 'IGST'; // ── UPI QR placeholder in invoice ── var upiQR = (upi && typeof QRCode !== 'undefined') ? '
Scan to pay: ' + upi + '
' : ''; var rcBanner = rc === 'yes' ? '
Reverse Charge: Tax payable by recipient under RCM
' : ''; var html2 = '
' + '
' + '
' + (logoHtml ? '
' + logoHtml + '
' : '') + '
TAX INVOICE
' + '
' + seller + '
' + (sellerG ? '
GSTIN: ' + sellerG + '
' : '') + (sellerP ? '
PAN: ' + sellerP + '
' : '') + (sellerC ? '
' + sellerC + '
' : '') + '
' + sellerA + '
' + '
' + '
' + '
Invoice No: ' + invNo + '
' + '
Date: ' + date + '
' + (dueD ? '
Due Date: ' + dueD + '
' : '') + (ps ? '
Place of Supply: ' + ps + '
' : '') + (po ? '
PO Ref: ' + po + '
' : '') + (eway ? '
E-Way Bill: ' + eway + '
' : '') + (veh ? '
Vehicle No: ' + veh + '
' : '') + '
' + '
' + rcBanner + '
' + '
' + '
Bill To
' + '
' + buyer + '
' + (buyerG ? '
GSTIN: ' + buyerG + '
' : '') + (buyerM ? '
Mob: ' + buyerM + '
' : '') + (buyerE ? '
' + buyerE + '
' : '') + '
' + buyerA + '
' + '
' + '
' + '
Ship To
' + '
' + buyer + '
' + '
' + shipA + '
' + '
' + '
' + '
' + '' + '' + '' + '' + '' + '' + '' + '' + '' + '' + '' + '' + '' + taxCols + '' + '' + '' + rows + '' + '
Sr.ProductSKUDescriptionHSN/SACQtyUnitRateDisc%TaxableGST%Total
' + '
' + '
' + '
Sub-Total (Taxable)' + cs + fmt(subTotal) + '
' + (totDisc > 0 ? '
Total Discount−' + cs + fmt(totDisc) + '
' : '') + (gstType === 'cgst_sgst' ? '
CGST' + cs + fmt(totTax / 2) + '
' + '
SGST' + cs + fmt(totTax / 2) + '
' : gstType === 'igst' ? '
IGST' + cs + fmt(totTax) + '
' : '') + (Math.abs(roundOff) > 0.001 ? '
Round Off' + (roundOff >= 0 ? '+' : '') + fmt(roundOff) + '
' : '') + '
Grand Total' + cs + fmt(final) + '
' + '
Amount in words: ' + numWords(Math.round(final)) + '
' + '
' + (upi || bank || payT ? '
' + '
Payment Information
' + (payT ? '
Terms: ' + payT + '
' : '') + (upi ? '
UPI: ' + upi + '
' : '') + upiQR + (bank ? '
Bank: ' + bank + '
' : '') + '
' : '') + (notes || terms ? '
' + (notes ? '
Notes: ' + notes + '
' : '') + (terms ? '
Terms & Conditions:
    ' + terms.split('\n').filter(function (l) { return l.trim(); }).map(function (l) { return '
  • ' + l.trim() + '
    • '; }).join('') + '
' : '') + '
' : '') + '
' + '
' + sigHtml + '
Authorised Signatory
' + seller + '
' + '
' + '
' + '
Computer-generated invoice. Powered by VasyERP Free Tools — vasyerp.com
' + '
'; document.getElementById('igPreview').innerHTML = html2; // Render UPI QR inside invoice if (upi && typeof QRCode !== 'undefined') { var qrDiv = document.getElementById('invUpiQR'); if (qrDiv) { qrDiv.innerHTML = ''; try { new QRCode(qrDiv, { text: 'upi://pay?pa=' + encodeURIComponent(upi) + '&pn=' + encodeURIComponent(seller) + '&am=' + final.toFixed(2) + '&tn=' + encodeURIComponent('Inv ' + invNo), width: 80, height: 80, colorDark: '#303335', colorLight: '#ffffff', correctLevel: QRCode.CorrectLevel.M }); } catch (e) { } } } document.getElementById('noteArea').textContent = 'Invoice ready \u00b7 ' + items.length + ' item(s) \u00b7 Total: ' + cs + fmt(final) + ' \u00b7 Download or Print below.'; document.getElementById('resultBox').classList.add('show'); document.getElementById('calcBtn').innerHTML = 'Generate Another '; saveHist(invNo, buyer, final, captureForm()); setTimeout(function () { document.getElementById('resultBox').scrollIntoView({ behavior: 'smooth', block: 'nearest' }); }, 100); updateStickyBar(true); } // ── printInvoice ───────────────────────────────────────────────────────────── function printInvoice() { openPrintWindow(); } // ── resetCalc ───────────────────────────────────────────────────────────────── function resetCalc() { ['igSellerName', 'igSellerGST', 'igSellerPAN', 'igSellerContact', 'igSellerAddr', 'igBuyerName', 'igBuyerGST', 'igBuyerMobile', 'igBuyerEmail', 'igBuyerAddr', 'igShipAddr', 'igInvNo', 'igDueDate', 'igPO', 'igEWay', 'igPayTerms', 'igUPI', 'igBank', 'igVehicle', 'igNotes', 'igTerms', 'igRC', 'igPS' ].forEach(function (id) { var el = document.getElementById(id); if (el) el.value = ''; }); document.getElementById('igItemsWrapper').innerHTML = ''; itemCount = 0; addItem(); document.getElementById('resultBox').classList.remove('show'); var btn = document.getElementById('calcBtn'); if (btn) btn.innerHTML = 'Generate Invoice '; var wrap = document.getElementById('upiQRWrap'); if (wrap) wrap.classList.remove('show'); var div = document.getElementById('upiQRDiv'); if (div) div.innerHTML = ''; updateStickyBar(false); localStorage.removeItem(AS_KEY); } // ── p27 compat ──────────────────────────────────────────────────────────────── function p27Copy() { shaLink(); } function p27WA() { shaWA(); } function p27LI() { window.open('https://www.linkedin.com/sharing/share-offsite/?url=' + encodeURIComponent(window.location.href), '_blank'); } // ── Init ────────────────────────────────────────────────────────────────────── document.addEventListener('DOMContentLoaded', function () { addItem(); renderHist(); var d = document.getElementById('igDate'); if (d && !d.value) d.value = new Date().toISOString().split('T')[0]; }); // ══════════════════════════════════════════════════════ // MOBILE-FIRST JS // ══════════════════════════════════════════════════════ // ── Auto-save draft ────────────────────────────────── var AS_KEY = 'vasy_inv_draft'; var autoSaveTimer = null; var autoSaveBusy = false; function autoSave() { clearTimeout(autoSaveTimer); autoSaveTimer = setTimeout(function () { try { var data = captureForm(); data._saved = new Date().toISOString(); localStorage.setItem(AS_KEY, JSON.stringify(data)); var badge = document.getElementById('autosaveBadge'); if (badge) { badge.classList.add('visible'); clearTimeout(badge._t); badge._t = setTimeout(function () { badge.classList.remove('visible'); }, 2500); } } catch (e) { } }, 900); } function restoreDraft() { try { var raw = localStorage.getItem(AS_KEY); if (!raw) return; var data = JSON.parse(raw); if (!data || !data._saved) return; // Check there's actual content worth restoring if (!data.igSellerName && !data.igBuyerName && !(data.items && data.items.length)) return; loadForm(data); var banner = document.getElementById('draftBanner'); var sub = document.getElementById('draftBannerSub'); if (banner) { var d = new Date(data._saved); if (sub) sub.textContent = 'Last saved: ' + d.toLocaleString('en-IN', { dateStyle: 'short', timeStyle: 'short' }); banner.classList.add('visible'); } } catch (e) { } } function dismissDraftBanner() { var b = document.getElementById('draftBanner'); if (b) b.classList.remove('visible'); } function clearDraftAndDismiss() { localStorage.removeItem(AS_KEY); dismissDraftBanner(); resetCalc(); } function attachAutoSave() { // Listen for any change/input on the form area var body = document.getElementById('calculator'); if (!body) return; ['input', 'change'].forEach(function (evt) { body.addEventListener(evt, function () { autoSave(); }, true); }); } // ── Sticky action bar state ────────────────────────── function updateStickyBar(generated) { var gen = document.getElementById('sabGenerate'); var dl = document.getElementById('sabDownload'); var sh = document.getElementById('sabShare'); var rst = document.getElementById('sabReset'); if (!gen) return; if (generated) { gen.style.display = 'none'; dl.style.display = ''; sh.style.display = ''; rst.style.display = ''; } else { gen.style.display = ''; dl.style.display = 'none'; sh.style.display = 'none'; rst.style.display = 'none'; } } // ── Inline validation ──────────────────────────────── function showFieldError(inputEl, msg) { inputEl.classList.add('invalid'); var wrapper = inputEl.closest('.field') || inputEl.parentElement; var errEl = wrapper.querySelector('.field-error'); if (!errEl) { errEl = document.createElement('div'); errEl.className = 'field-error'; wrapper.appendChild(errEl); } errEl.textContent = msg; errEl.classList.add('visible'); } function clearFieldError(inputEl) { inputEl.classList.remove('invalid'); var wrapper = inputEl.closest('.field') || inputEl.parentElement; var errEl = wrapper.querySelector('.field-error'); if (errEl) errEl.classList.remove('visible'); } function validateGSTIN(val) { // Basic GSTIN format: 15 chars, digits 1-2 are state code, format: 99XXXXX9999X9X9 return !val || /^[0-9]{2}[A-Z]{5}[0-9]{4}[A-Z]{1}[1-9A-Z]{1}Z[0-9A-Z]{1}$/.test(val.toUpperCase()); } function validateEmail(val) { return !val || /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(val); } function validateMobile(val) { return !val || /^[6-9]\d{9}$/.test(val.replace(/\s/g, '')); } function attachValidation() { // GSTIN fields ['igSellerGST', 'igBuyerGST'].forEach(function (id) { var el = document.getElementById(id); if (!el) return; el.addEventListener('blur', function () { var v = el.value.trim().toUpperCase(); if (v) el.value = v; if (!validateGSTIN(v)) showFieldError(el, 'Invalid GSTIN format (e.g. 27AABCU9603R1ZM)'); else clearFieldError(el); }); el.addEventListener('input', function () { if (el.classList.contains('invalid')) clearFieldError(el); }); }); // Email var eEl = document.getElementById('igBuyerEmail'); if (eEl) { eEl.addEventListener('blur', function () { if (!validateEmail(eEl.value.trim())) showFieldError(eEl, 'Please enter a valid email address'); else clearFieldError(eEl); }); eEl.addEventListener('input', function () { if (eEl.classList.contains('invalid')) clearFieldError(eEl); }); } // Mobile var mEl = document.getElementById('igBuyerMobile'); if (mEl) { mEl.addEventListener('blur', function () { var v = mEl.value.trim(); if (v && !validateMobile(v)) showFieldError(mEl, 'Enter a valid 10-digit Indian mobile number'); else clearFieldError(mEl); }); mEl.addEventListener('input', function () { if (mEl.classList.contains('invalid')) clearFieldError(mEl); }); } } // ── iOS PDF fix: use blob + object URL approach ────── function iosSafePDF() { openPrintWindow(); toast('Opening print dialog \u2014 select Save as PDF'); } function dlPDF() { openPrintWindow(); toast('Opening print dialog \u2014 select Save as PDF'); } // ── Single null-safe print/PDF entry point ──────────── function openPrintWindow() { var previewEl = document.getElementById('igPreview'); if (!previewEl || !previewEl.innerHTML.trim()) { toast('Please generate an invoice first'); return; } var content = previewEl.innerHTML; var docStr = '' + 'Invoice - VasyERP' + '' + content + ' '; // Try window.open — may return null if popups are blocked var w = window.open('', '_blank'); if (w && w.document) { try { w.document.open(); w.document.write(docStr); w.document.close(); w.focus(); setTimeout(function () { w.print(); }, 600); } catch (e) { w.close(); blobFallback(docStr); } return; } // Popup blocked — try Blob URL (works on most Android/Desktop browsers) blobFallback(docStr); } function blobFallback(docStr) { try { var blob = new Blob([docStr], { type: 'text/html;charset=utf-8' }); var url = URL.createObjectURL(blob); var a = document.createElement('a'); a.href = url; a.target = '_blank'; a.rel = 'noopener'; document.body.appendChild(a); a.click(); document.body.removeChild(a); setTimeout(function () { URL.revokeObjectURL(url); }, 10000); } catch (e) { toast('Enable pop-ups for this site to print / save PDF'); } } // resetCalc sticky bar update: handled inline in main resetCalc() above // calculate sticky bar update: handled inline in main calculate() above // ── Apply inputmode after addItem (called directly) ── function applyInputmodeToItem() { // Apply inputmode to the newly created item's number fields var id = itemCount; var numFields = ['qty', 'rate', 'disc']; numFields.forEach(function (f) { var el = document.getElementById(f + '-' + id); if (el) { el.setAttribute('inputmode', 'decimal'); el.setAttribute('autocorrect', 'off'); el.setAttribute('autocomplete', 'off'); } }); var nameEl = document.getElementById('name-' + id); if (nameEl) { nameEl.setAttribute('inputmode', 'text'); nameEl.setAttribute('autocapitalize', 'words'); nameEl.setAttribute('autocorrect', 'off'); nameEl.setAttribute('autocomplete', 'off'); } var skuEl = document.getElementById('sku-' + id); if (skuEl) { skuEl.setAttribute('inputmode', 'text'); skuEl.setAttribute('autocorrect', 'off'); skuEl.setAttribute('autocomplete', 'off'); } var hsnEl = document.getElementById('hsn-' + id); if (hsnEl) { hsnEl.setAttribute('inputmode', 'numeric'); hsnEl.setAttribute('autocorrect', 'off'); hsnEl.setAttribute('autocomplete', 'off'); } var sdescEl = document.getElementById('sdesc-' + id); if (sdescEl) { sdescEl.setAttribute('inputmode', 'text'); sdescEl.setAttribute('autocapitalize', 'sentences'); sdescEl.setAttribute('autocorrect', 'on'); } autoSave(); } // ── DOMContentLoaded ───────────────────────────────── document.addEventListener('DOMContentLoaded', function () { // Add addItem + renderHist + date (from main init) // These are already done by the main init block above, // so just attach extra mobile behaviors here: attachAutoSave(); attachValidation(); // Draft restore (slight delay so form is initialized) setTimeout(restoreDraft, 150); // Show sticky bar on mobile if (window.innerWidth <= 900) { var bar = document.getElementById('stickyBar'); if (bar) bar.classList.add('visible'); } // Prevent double-tap zoom on buttons document.querySelectorAll('button, .btn-primary, .btn-outline').forEach(function (el) { el.addEventListener('touchend', function (e) { e.preventDefault(); el.click(); }, { passive: false }); }); }); window.addEventListener('resize', function () { var bar = document.getElementById('stickyBar'); if (!bar) return; if (window.innerWidth <= 900) bar.classList.add('visible'); else bar.classList.remove('visible'); });