Nager.Date vs UK Bank Holidays

Nager.Date is a free, open-source public holiday API covering more than 100 countries, with endpoints for a year's full holiday list, the next public holiday, whether today is a holiday, and country/county metadata — all keyless JSON with no rate limiting. It's maintained on GitHub by a single developer and is popular as the default holiday backend baked into several scheduling and HR libraries specifically because it needs no signup.

The UK government publishes England & Wales, Scotland, and Northern Ireland bank holidays as a single static JSON file at gov.uk, listing each holiday's date, title, and whether it's a “substitute day” moved from a weekend. It's official, authoritative, and requires nothing beyond an HTTP GET — no key, no rate limit, and it's licensed under the Open Government Licence for reuse including commercially.