One box that writes or rewrites
The same box does both jobs, and it works out which one you meant from whether the form already has anything in it.
On an empty form it drafts the whole invoice: your business, the client, itemised lines with quantities and rates, the tax rate, and the terms you described. Nothing needs to be filled in first.
On an invoice you already have it edits in place. "Add two more hours to the second line", "change the due date to net 30", "drop the discount and add 8.25% sales tax" — it changes what you asked about and leaves the rest alone.
Why the numbers are trustworthy
The usual objection to an AI invoice is that language models are bad at arithmetic. That objection does not apply here, by design.
The model is never allowed to do the maths. It returns a tax rate — never a tax amount, never a subtotal, never a total. Every figure on the finished invoice is computed by the app from the line items, in integer minor units, the same code path as an invoice you typed by hand. A model that is bad at multiplication cannot produce a wrong total here, because it is never asked for one.
You also get a plain-language summary of exactly what changed — "Added a line item", "Changed the due date" — generated by diffing the invoice before and after, not by asking the model what it says it did. And an Undo button that restores the previous version exactly, including the styling.
What gets sent, and when
Only the text you type in the AI box, and only at the moment you click Ask AI. It goes to our gateway, a model drafts or edits the invoice, and the result comes straight back — none of it is stored. The rest of the app never contacts a server: editing, saving, sharing, PDF export and the client's view of the invoice all happen in the browser. The AI is entirely optional, and the form works exactly the same without it.
Questions
Can the AI get my totals wrong?
It cannot produce the totals at all. The model returns line items and a tax rate; the app computes every subtotal, discount, tax amount and total itself in integer minor units. Arithmetic never passes through the model.
Do I need an account to use the AI invoice generator?
No. There is no signup and no email address for any part of the app, the AI included. It is free and there is no cap on how many invoices you draft.
Is my invoice sent to a server when I use AI?
The text you type in the AI box is sent when you click Ask AI, and only then, so a model can draft or edit the invoice. Nothing is stored. If you do not use the AI box, nothing you type ever leaves your browser.
Can it edit an invoice I already started?
Yes. Describe the change in the same box — "add two hours to the second line", "make it net 30" — and it edits that invoice rather than starting over. A summary shows what changed and Undo restores the previous version.
What should I type to get a good invoice?
Plain English works. Say who it is for, what the work was, the quantities and rates, and the terms: "12 hours of finish carpentry at $65/hr plus $180 of materials for Ana Fields, due in 14 days". Missing details you can just fill in on the form afterwards.
Does the AI work for receipts, quotes and bills of sale too?
Yes — the receipt, quote and bill of sale generators each have the same box, with the same rules about the app doing the arithmetic and Undo restoring the previous version.