What RegexParser is
A free regex workbench that runs your regular expression in the engine it is meant for: the JavaScript RegExp of your browser, and pinned WebAssembly builds of Python re (CPython 3.14.2 in Pyodide), PCRE2 10.48 and Go 1.27.1 regexp.
It shows every match and capture, explains the pattern from its parse tree, compares engines, keeps regression tests and exports code that reproduces a result.
What it does not claim
It is not affiliated with the projects whose engines it runs. A pinned engine build is that engine at that version, not every environment that embeds it (for example, PCRE2 is not PHP preg).
Explanations cover the grammar the parser understands; anything outside it is marked as not explained rather than guessed. Equal results on your samples are reported as "Same on these samples", never as equivalence.
Contact
Seadfeng · support@regexparser.com
Last changed 2026-09-27.