IP.APP API Free easy to use API to check your IP address
HTTP Status Pizzas API Pizzas for every HTTP response status code.
HTTP Response API Test how your code reacts to varying HTTP responses
HTTP Status Ducks API Ducks for every HTTP response status code
HTTP Status Goats API Goats - yes goats! - for every HTTP status code.
HTTP Documentation HyperText Transfer Protocol (HTTP) explained, with examples
http.garden Gardening for every HyperText Transfer Protocol status code
HTTP Status Cats A cat image for every HTTP status code
HTTP Status Dogs Dogs for every HyperText Transfer Protocol status code.
CLS Debugger Test and debug Cumulative Layout Shifts, by ex-Google.
HTTP Status Tester Test URLs in bulk for their HTTP responses, by ex-Google
URL Parse API Easily parse a URL into its components, by ex-Google