“Create Professional invoices with our Free GST invoice generator Online tool. GSTIN auto-detect. CGST/SGST/IGST auto-calculation. No login, no watermark, no limit.”

Free GST Invoice Generator Online — Everything You Need to Know

If you run a business in India — whether you are a freelancer, a shop owner, a consultant, or a small trader — you have to issue GST invoices. There is no way around it. And doing it manually in Excel or Word? That is just asking for errors, penalties, and a very unhappy CA.

This free GST invoice generator does all the heavy lifting for you. Enter your details, add your items, and download a professional PDF invoice in under two minutes. No signup. No watermark. No hidden charges. No limit. Just a clean, GST-compliant invoice ready to send.

What Exactly is a GST Invoice?

A GST invoice is a legal document that a GST-registered seller issues to a buyer when goods or services are supplied. It is not just a bill — it is the document your buyer needs to claim Input Tax Credit (ITC). If your invoice has a mistake or a missing field, your buyer cannot claim ITC, and that creates a very uncomfortable conversation.

Under GST Rule 46 of the CGST Rules, every tax invoice must include specific mandatory fields. Miss even one, and the invoice is non-compliant. This tool automatically covers all of them.

What Goes Into a Valid GST Invoice?

A lot of businesses get this wrong. Here is exactly what a valid GST invoice must have:

Your business name, address, and GSTIN. The invoice number — which cannot exceed 16 alphanumeric characters and must be unique for each financial year. The invoice date. Your buyer’s name, address, and GSTIN (mandatory for B2B, and for B2C invoices above ₹50,000).

The HSN code for goods or SAC code for services. A clear description of the goods or services with quantity and rate.

The taxable value, GST rate, and the split — CGST and SGST for same-state sales, or IGST for different-state sales. The place of supply. Whether reverse charge applies. And the grand total.

This tool fills in and calculates all of this automatically. You just enter the business details and items — everything else is handled.

CGST, SGST, and IGST — What is the Difference?

This is the question that confuses most people. The rule is actually simple.

When your business and your buyer are in the same state, GST is split into two equal parts — CGST (Central GST) and SGST (State GST). So if the GST rate is 18%, you charge 9% CGST and 9% SGST.

When your business and your buyer are in different states, only IGST (Integrated GST) applies. The full 18% goes as IGST.

The good news is you do not need to figure this out manually. The moment you enter your buyer’s GSTIN, this tool reads the state code from it, compares it with your state, and automatically applies the right tax. CGST and SGST if you are in the same state. IGST if you are not. It is completely automatic.

Why HSN and SAC Codes Matter (And What Happens If You Skip Them)

HSN stands for Harmonized System of Nomenclature — it is the code used to classify goods. SAC stands for Services Accounting Code — for services. These codes determine which GST rate applies to your product or service.

Skipping them is not an option. A missing or incorrect HSN code attracts a penalty of ₹50 per invoice under Section 125 of the CGST Act — with a maximum cap of ₹25,000 per year. That adds up fast if you issue invoices regularly.

The digit requirement also depends on your annual turnover. If your AATO (Annual Aggregate Turnover) is up to ₹5 crore, a 4-digit HSN code is sufficient for B2B invoices. Above ₹5 crore, you need 6 digits. For exports and SEZ supplies, 8 digits are required regardless of turnover.

B2B vs B2C Invoice — What Changes?

A B2B invoice is issued to a GST-registered buyer — someone who has a valid GSTIN. A B2C invoice is for unregistered buyers or end consumers.

For B2B invoices, the buyer’s GSTIN is mandatory on the invoice. For B2C invoices below ₹50,000, it is optional. But the moment your B2C invoice crosses ₹50,000, GST Rule 46 requires you to mention the buyer’s address and state code on the invoice. This tool shows a warning automatically when this threshold is crossed.

A Note on E-Invoicing for Larger Businesses

If your business turnover crosses ₹5 crore (AATO), e-invoicing is mandatory as per CBIC notification. You need to generate your invoice through the IRP (Invoice Registration Portal), which gives you an IRN number and a signed QR code that must appear on the invoice.

Additionally, from April 2025, businesses with turnover above ₹10 crore must upload every invoice to the IRP within 30 days of the invoice date. Late uploads are simply rejected — and your buyer cannot claim ITC on them.

If you fall under these categories, use this tool to prepare your invoice details, then upload to the IRP for the IRN and QR code before sending to your buyer.

How to Use This GST Invoice Generator — Step by Step

Using this tool takes about two minutes if your details are ready.

Start by entering your business details in the first section — your business name, GSTIN, address, and optionally your mobile and email. You can also upload your business logo. The tool saves your details automatically so you do not have to re-enter them every time.

Next, fill in your buyer or client details. Enter their GSTIN and the tool will auto-detect the state and set the place of supply. It will also tell you instantly whether it is a B2B or B2C transaction.

Then add your items. For each line item, enter the description, HSN or SAC code, quantity, unit, and rate. Select the GST rate from the dropdown — the tax is calculated instantly and shown in real time.

If your buyer pays you directly to your bank, you can add your bank details in the next section. These will appear at the bottom of the printed invoice.

Finally, check the summary on the right side. You will see the taxable value, GST breakdown (CGST and SGST or IGST), and the grand total with the amount written in words. When everything looks right, click Generate and Print. A professional invoice opens in a new view — click Print or Save as PDF to download it.

Who Should Use This Tool?

This GST invoice generator is built for anyone who needs to issue GST-compliant invoices without the cost or complexity of full billing software.

Freelancers and consultants who issue a handful of invoices every month will find this the fastest option — no subscription, no learning curve. Small shop owners and traders who need proper B2B invoices for their buyers. Service providers in IT, design, marketing, logistics, and other sectors. Startups that are not ready to invest in accounting software but need compliant invoices from day one. Even established businesses can use this for quick invoices when their main system is unavailable.

If you need to track invoices, manage inventory, file GSTR-1, or handle full accounting — you will eventually need proper billing software. But for creating a clean, compliant GST invoice fast, this tool does exactly what it needs to do.

Frequently Asked Questions (FAQs) – Invoicing & Rules