How to Use the Online Invoice Generator Free: A Step-by-Step Walkthrough
Reviewed by the FreeOnline.fyi team · Updated 2026-09-10
We built the [Online Invoice Generator Free](https://freeonline.fyi/online-invoi
We built the Online Invoice Generator Free because most freelancers we know don't actually enjoy making invoices — they enjoy the ten minutes after the invoice gets paid. The tool runs entirely in your browser, so there is no account to create, nothing gets uploaded to a server, and a half-finished invoice quietly survives a page refresh thanks to localStorage. In this walkthrough we'll show you, step by step, how to go from a blank page to a print-ready PDF in under two minutes.
If you want a quick tour of every other utility on the site first, head over to FreeOnline.fyi free online tools. And if a client ever sends you a PDF invoice that you need to edit, our PDF to Word Converter (Free, No Registration) pairs nicely with this generator.
The first block on the left is "Your business details." Fill in your trading nam
The first block on the left is "Your business details." Fill in your trading name, postal address, email and — if you are VAT-registered — your VAT number and optional company number. Nothing here is sent anywhere; the fields simply render into the header of the invoice preview on the right. We tested it with a typical sole trader setup and found that a one-line address plus a postcode is enough to look credible to most UK clients. If you operate as a limited company, drop your Companies House registration number in too — it is not mandatory, but it tends to speed up payment from larger clients who run compliance checks.
A small note on VAT numbers: the UK format is nine digits, sometimes written with the "GB" prefix in front. If you are not registered for VAT, just leave the field blank and set the VAT rate to 0% further down. For reference, HMRC explains who must register and when on the gov.uk VAT registration page.
Below your details you'll see "Bill to" and "Invoice details" sitting next to ea
Below your details you'll see "Bill to" and "Invoice details" sitting next to each other. The invoice number is auto-generated as INV-YYYYMMDD-XXX using today's date plus a short random suffix, so two invoices opened in the same minute will not collide. The issue date defaults to today and the due date defaults to 14 days later — which matches the 14-day payment term we pre-fill in the notes box at the bottom. You can overwrite any of these defaults. Currency defaults to GBP, and you can switch to USD or EUR; the totals on the right recalculate immediately and the currency symbol updates everywhere at once.
The "Bill to" block is straightforward: client name, address and optional email. We deliberately made the email optional because many freelancers invoice through accounting software that handles delivery separately. If you do include it, it appears in the rendered invoice as a clickable mailto link when you export.
Now the part that matters most: line items.
Now the part that matters most: line items. Each row has a description, a quantity and a rate. As you type, the right-hand preview recomputes the subtotal, the VAT line and the grand total on every keystroke — no need to click a "calculate" button. A typical example: a freelance designer billing 8 hours at £65 per hour produces a subtotal of £520, a VAT line of £104 at the default 20% rate, and a grand total of £624.00. If you add a second line for a fixed-fee deliverable of £250, the new subtotal becomes £770, VAT £154, total £924.00 — all without any input on your part. The VAT rate field accepts values between 0 and 20 in 0.5% steps, which covers the UK standard rate (20%), reduced rate (5%) and zero rate, so you can stay compliant with the rates listed on gov.uk VAT rates.
If a client asks you to back out VAT — for example because they are overseas and reverse-charge applies — set the rate to 0%. The grand total will then equal the subtotal, and you can add a short note such as "Reverse charge: customer to account for VAT" in the notes box below. That note is free-form and appears as a footer on the printed invoice.
When everything looks right, hit the "Print / Save as PDF" button.
When everything looks right, hit the "Print / Save as PDF" button. The button triggers window.print() with a dedicated print stylesheet that hides the left-hand form, removes buttons, and reformats the preview into a clean A4 layout with sensible margins. In the print dialog, choose "Save as PDF" as the destination in Chrome or Edge, or "Print to PDF" in Safari on macOS, and you have a file you can email straight to your client. The "Reset" button clears every field and returns the form to its defaults — useful if you want to start a fresh invoice after finishing one.
A few honest limitations worth mentioning. The tool does not chase payments, send automatic reminders, or reconcile against your bank account — for that you would need dedicated accounting software. It also does not store any invoices for you; the moment you close the tab, the only persistent copy is the PDF you saved. If you need a longer-term record, save the PDF with a recognisable filename such as INV-20250610-001-acme-corp.pdf and back it up somewhere safe. And because the maths happens in your browser, the numbers you see are the numbers that get printed — there is no server-side recomputation, so verify the grand total against your own arithmetic before sending it to a client worth thousands.
In short: enter your business, enter the client, add line items, watch the total
In short: enter your business, enter the client, add line items, watch the totals update live, then print or save as PDF. The whole flow takes about two minutes once you have used it a couple of times, and there is no account standing between you and a professional-looking invoice.