What this calculator does not do
- It does not know your public holidays, and it will not. They depend on the country, often on the region inside it, and on the year. A calculator that skipped the wrong country's holidays would be wrong in a way that looks authoritative, which is worse than skipping none. Take them off the answer here yourself.
- It does not know your working week. Monday to Friday is hard-coded, so it is wrong anywhere the weekend falls on Friday and Saturday, or on Thursday and Friday.
- It does not keep anything. Nothing is written to your browser's storage while you use it and nothing is sent to us, so the dates are gone when you close the tab.
Related
For a payment due date rather than a plain working-day count, the invoice due date calculator takes Net terms, end-of-month terms and a working-day option. Once that date has gone past, the late payment fee calculator works out what the invoice is worth now.
Last updated 21 September 2026