Invoice Generator
A clear invoice gets you paid faster: it says who is billing whom, what for, how much is owed, when it is due and how to pay. This generator builds one on the page as you type — your details, a bill-to block, line items with quantity and unit price, an optional discount and tax, shipping, and notes for payment instructions — and calculates every total for you. When it looks right, print it or choose “Save as PDF” in your browser’s print dialog. Everything stays in your browser: nothing is uploaded, stored or shared, and there is no account, watermark or limit.
How to use the invoice generator
- Fill in your details and your client’s details, the invoice number and the dates.
- Add one line item per line in the form “description | quantity | unit price”. The calculator multiplies quantity by price and adds them up.
- Enter any tax or VAT/GST percentage, discount percentage and shipping or other charges, and choose a currency.
- Check the preview, then press “Print / save as PDF”. Choose “Save as PDF” as the printer to get a file you can email.
- Keep a copy and number invoices sequentially for your records.
Formula
Line amount = quantity × unit price. Subtotal = sum of line amounts. Discount = subtotal × discount%. Tax = (subtotal − discount) × tax%. Total = subtotal − discount + tax + shipping. Tax is applied after the discount, which is how most invoices are taxed; if your jurisdiction differs, set the discount to 0 and add a negative-priced line instead.
Worked examples
Three line items with VAT
Design 1 × 1,200, hosting 1 × 180 and 3 revisions at 45.50 give a subtotal of £1,516.50. Adding 20% VAT (£303.30) gives a total of £1,819.80.
Discount before tax
Two items of 349.50 with a 10% discount, 10% tax and 5 shipping: discount comes off first (to 314.55), tax is charged on that, and shipping is added: total $351.01.
An hourly consulting invoice
Consulting 12.5 hours at $90 an hour is $1,125.00 — quantity can be a decimal for hours.
What to put on an invoice
| Item | Why it matters |
|---|---|
| Unique invoice number | Lets both sides track and reconcile payments |
| Issue and due dates | Sets the payment deadline |
| Your and your client’s details | Needed for accounts and, often, tax records |
| Clear descriptions and prices | Avoids disputes |
| Tax registration number and rate | Required in many countries when you charge VAT, GST or sales tax |
| Payment instructions and terms | Makes it easy to pay and states late-fee rules |
Charging tax? Check the amounts with our VAT, GST and sales tax calculators. Invoice rules vary by country, so confirm requirements with your tax authority.
Common mistakes to avoid
- Leaving off the invoice number or dates. Sequential numbers and clear due dates help both you and your client’s accounts team.
- Forgetting the payment details. If it is not obvious how to pay, payment is slower.
- Charging the wrong tax. Whether you must add VAT, GST or sales tax depends on your registration and location — check with your accountant or tax authority.
- Not stating payment terms (for example “due in 14 days” and any late-payment fee).
- Sending without a copy. Keep your own records for the length of time your tax authority requires.
Frequently asked questions
Is this invoice generator free?
Yes. There is no sign-up, watermark or limit, and nothing is uploaded — it runs in your browser.
How do I save the invoice as a PDF?
Press “Print / save as PDF”, then choose “Save as PDF” as the destination in your browser’s print dialog.
Is my invoice data stored?
No. The data stays on your device and disappears when you close or reload the page, so save the PDF before you leave.
What should an invoice include?
Your details, the client’s details, a unique invoice number, issue and due dates, a description of the goods or services with quantities and prices, totals with any tax, and payment instructions. Tax registration numbers may also be legally required in your country.
How is tax calculated?
As a percentage of the subtotal after any discount. Enter your VAT, GST or sales tax rate; our VAT, GST and sales tax calculators can help you check the amounts.
Is this legal or tax advice?
No. Invoice requirements vary by country; check with your accountant or tax authority.
Reviewed September 26, 2026 by the SolveCalcPro editorial team. Found a mistake? Tell us; see our editorial policy.