Check a UK visa: official tools

How do you check if you need a UK visa?

GOV.UK has an official checker ("Check if you need a UK visa") that tells you, based on your nationality and the purpose/length of your trip, whether you need a visa, an ETA, or neither. It's a simple questionnaire, not an account login.

If you already have a visa and need to check its status or conditions, that is normally done through the UK Visas and Immigration account you used to apply, not a general public checker — there isn't an open "look up any visa" tool for privacy reasons.