Invoice Number Generator
Generate a batch of sequential invoice numbers with a consistent prefix and digit format — useful for setting up a numbering system before your first invoice, or picking up a consistent sequence after switching tools.
The calculation, explained
Each number combines your prefix with the starting number, incrementing by 1, padded to your chosen digit count (e.g. digit count 4 turns “7” into “0007”). A consistent format makes your invoices easier to sort and search later.
Common questions
Do invoice numbers need to be sequential?
Not legally in most jurisdictions, but sequential numbering is standard practice and makes it obvious if an invoice is missing from your records.
Can I restart my numbering each year?
Yes — many businesses use a prefix like the year (INV-2026-0001) and reset the sequence annually. Just set your starting number and prefix accordingly here.
Turn this into a real invoice.
Use the full generator to build a proper, line-itemized invoice — free, no signup.