Regex Visualizer & Test Bench

Test a pattern against sample text, see matches and groups, then copy the wrapper code for the language you are actually shipping — not a screenshot of a match list.

Regex Visualizer & Test Bench

Highlight matches and groups, then copy wrapper code for JS, Python, PHP, Go, Java, and Rust.

Highlighted text

Matches will highlight here.

Tester runs the JavaScript regex engine. Snippets are wrappers, not a guarantee that every construct exists in PHP or Go.

Matching is not the hard part

A regex tester that only highlights is half the job. The other half is the call site: String.prototype.matchAll vs re.sub vs preg_match_all vs FindAllStringSubmatch. Those APIs disagree about flags, about how you write a replacement, and about whether you need g.

This bench keeps the JavaScript flavor in the tester (what the browser can run) and prints idiomatic wrappers for Python, PHP, Go, Java, and Rust from the same pattern. Dialects are not identical — lookbehind, Unicode classes, and possessive quantifiers can differ. Treat the snippet as a starting point, then run it in the target runtime.

Habits that still apply

  • Anchor when you mean the whole string (^, $).
  • Add flags on purpose. g in JavaScript is finditer / FindAll elsewhere, not a silent default.
  • Catastrophic backtracking is still a thing. Keep the test corpus small until the pattern is stable.

If you only need a quick highlight, the smaller Regex Tester is enough.