Regex Playground vs RegexPlanet

Regex Playground has no write-up on Specifiction yet; its figures are above.

RegexPlanet is a free web service for testing regular expressions during development. It offers separate test pages for engines including Java, Python, Bun, Go, Deno, Erlang, Haskell, MySQL, .NET, Node.js, Perl, PHP, PostgreSQL, Ruby, Rust, Swift, Tcl, XRegExp, and the browser. The Java tester accepts a pattern, replacement, and multiple input strings, with a control for adding more inputs. Options include case-insensitive matching, multiline mode, and Unicode-aware case folding. The home page provides a field for share codes, and the site directs users to Regex Zone for sharing expressions and finding patterns. A status page reports engine status and says each engine runs separately. RegexPlanet warns that malformed expressions may run indefinitely and that some engines or hosts may face denial-of-service attacks. Its privacy policy describes collection of IP addresses, browser data, and form entries; raw logs are stored by Google CloudRun. The service is offered as-is and as-available.