Invoice numbering generator
Build an invoice numbering scheme (prefix, year or month, counter) and preview a full sequence of consecutive numbers before using them. 100% local processing in your browser — nothing is sent to a server.
How it works
Regulations generally require continuous, gap-free invoice numbering, often reset at the start of each accounting year. This tool helps you preview in advance what your full sequence will look like (prefix, optionally the year or month, then an incrementing counter) before applying it in your invoicing software.
Does this tool automatically number my actual invoices?
No, it only generates a preview of the number sequence in your browser, which you then copy into your invoicing software or spreadsheet. It doesn't keep any history or persistent counter from one session to the next.
Why include the year or month in the invoice number?
Including the year (or even the month) makes invoices easier to sort chronologically at a glance and follows a common accounting practice, where numbering often restarts at 1 each new accounting year. The simple "Prefix-Number" format suits continuous numbering over several years with no restart.
No invoicing data is sent to a server: the sequence is calculated entirely in your browser.