Commercial invoice guide — step by step | Itqan

Need a professional commercial invoice without heavy accounting software? The invoice calculator on Itqan creates invoices in any language with line items, discounts, a company logo, and one-click print or image export. This guide explains invoice types, real-world workflows, field-by-field tips, and how the tool differs from the VAT calculator and receipt voucher — written manually for our users, not copied from elsewhere.

What is the invoice calculator?

The invoice calculator builds a printable commercial invoice in your browser — seller and buyer details, line items, discounts, tax, and a design template. Totals calculate automatically; no spreadsheet formulas needed.

Different from the VAT calculator (single-amount tax math) — here is a full multi-line document. Different from the receipt voucher (payment proof) — an invoice is a bill issued before or at sale, not after collection.

When do you need an invoice?

• Freelancer: Bill a client after delivering a project or milestone.
• Small shop: Document a cash or credit sale to a walk-in customer.
• Service business: Invoice for maintenance, consulting, design, or training.
• Pre-contract estimates: Use the quotation type before final approval.
• Tax compliance: Issue a tax invoice with VAT line items and tax ID fields.
• Record keeping: Keep a printed or saved image copy for your books.

Supported invoice types

Choose the type that matches your transaction before filling in details.

• Standard invoice: A regular sale or service bill — the default for most businesses.
• Tax invoice: Includes tax ID fields and VAT breakdown for compliance in countries like Saudi Arabia (15% VAT).
• Cash invoice: Marks the transaction as paid immediately — common in retail.
• Credit invoice: Payment is due later; include a due date so the customer knows when to pay.
• Quotation: A price estimate before the contract is signed — not a final invoice. Convert to a standard or tax invoice after approval.

Line items work the same across all types — the type mainly changes tax fields and payment terms.

Real-world scenarios — step by step

Freelance web design — standard invoice after delivery

A designer finishes a three-page website. They open the invoice calculator, choose standard, enter trade name and logo (PNG under 2 MB), and add lines: “Homepage — 1 × 1,500”, “Contact page — 1 × 800”, “Mobile setup — 1 × 600”. They save the result as an image and email it. After payment, they issue a receipt voucher.

Retail shop — cash sale with logo

An electronics shop sells a laptop and accessories for cash. They select cash invoice, upload the store logo, and list items with quantities and prices. They print from the result page and hand the customer a copy, keeping a saved image in their daily sales folder.

Tax invoice for a Saudi business

A Riyadh consulting firm bills a corporate client with 15% VAT. They choose tax invoice, enter VAT registration numbers for seller and buyer, and add net line items — the tool adds VAT automatically. Totals can be verified with the VAT calculator. The client receives a PDF via browser print → Save as PDF.

Quotation before a project starts

A marketing agency pitches a six-month social media package. They issue a quotation (estimate valid 30 days) — not a final invoice. After client approval, they switch to tax or standard, copy the same lines, assign a new invoice number, and send the binding bill.

How to create an invoice on Itqan

1. Open the invoice calculator.
2. Choose the invoice type: standard, tax, cash, credit, or quotation.
3. Fill your business data — trade name, address, phone, email, tax ID if applicable — and upload your logo (PNG or JPG, max 2 MB).
4. Enter customer name, address, and any buyer tax ID required for tax invoices.
5. Add line items: description, quantity, unit price, and discount per line if needed.
6. Set currency, invoice number, date, and due date (for credit invoices).
7. Pick a template design and review the live preview.
8. Click Result — then print or save as image from the result page.

Free in the browser — no account required.

Important fields explained

Your business

Trade name, address, phone, email, and tax ID — shown in the header with your logo.

Customer

Name and address — required for credit and tax invoices; corporate buyers need their tax ID for VAT claims.

Line items

Description, quantity, unit price — totals auto-calculate. Mix products and services on one invoice.

Discounts and tax

Per-line or total discount. Tax invoices add VAT (typically 15% in Saudi Arabia). Verify single amounts with the VAT calculator if needed.

Logo

PNG or JPG up to 2 MB. Compress large files before uploading.

After creating the invoice

• Print: Use the print button on the result page for a paper copy.
• Save as image: Download an image file to share via WhatsApp, Telegram, or email.
• PDF: Use your browser’s print dialog and choose “Save as PDF” for an archival copy.
• Receipt voucher: After the customer pays, issue a receipt voucher as proof of payment received.
• Archive: Store the PDF or image with your invoice number in a dated folder for tax season.

Invoice calculator vs other Itqan tools

Invoice = full document with lines and branding. VAT calculator = quick single-amount math. Receipt voucher = proof after payment.

Common mistakes

Missing tax ID on a tax invoice

Tax invoices without a valid seller or buyer tax number may be rejected in an audit. Always fill mandatory tax fields for your country before generating.

Using a quotation as a final invoice

A quotation is an estimate — it is not a binding sales document. After client approval, create a new standard or tax invoice with a proper invoice number.

Oversized logo file

The upload limit is 2 MB. Compress or resize large PNG files so the preview loads quickly and the printed header stays sharp.

Wrong type for payment terms

Use credit (not cash) when payment is still pending — set a due date.

Practical tips

• Keep business data and logo in a folder for quick copy-paste.
• Use sequential invoice numbers (INV-2026-001, 002…) for easier tracking.
• Preview currency, tax, discounts, and customer spelling before sending.
• When converting a quotation, keep line descriptions identical.
• Works on mobile — create and save an image directly from your phone.

Before sending checklist

Before you click Result:

• Selected the correct type: standard, tax, cash, credit, or quotation.
• Business name, address, and tax ID (if required) are complete and accurate.
• Logo uploaded — PNG or JPG, under 2 MB.
• Customer name and address filled in; buyer tax ID added for B2B tax invoices.
• Every line item has a clear description, correct quantity, and unit price.
• Discounts and tax rate reviewed in the preview.
• Invoice number and date set; due date added for credit invoices.
• Currency matches what you agreed with the customer.

After you generate the invoice:

• Opened the result page and confirmed totals match your expectation.
• Printed, saved as image, or exported to PDF as needed.
• Sent the document to the customer through your usual channel.
• Archived a copy with the invoice number in your records.
• Planned a receipt voucher once payment is received.

Frequently asked questions

Summary

The invoice calculator on Itqan Tools lets you create professional commercial invoices — standard, tax, cash, credit, or quotation — with multiple line items, discounts, a company logo (PNG/JPG up to 2 MB), and one-click print or image export. It is free, runs in the browser, and needs no account. Use it for freelancing, retail, Saudi VAT compliance, or pre-project quotations. For quick single-amount tax math, use the VAT calculator; for proof of payment after collection, use the receipt voucher. Follow the checklist, pick the right invoice type, and keep a saved copy for your records.

Related tools

• VAT calculator
• Receipt voucher
• Percentage calculator