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100% Client-SideSandboxed Web WorkerReDoS Guarded

Regex Tester & Debugger

Type a pattern and matches highlight in real time with alternating colors and underlined capture groups. Every evaluation runs off the main thread and is hard-terminated after two seconds, so even catastrophic patterns can never freeze your browser.

  • Native JavaScript engine

    The same V8 RegExp your console runs — what you test is what ships.

  • ReDoS-guarded worker

    Sandboxed evaluation, hard-terminated at the 2-second budget.

  • Live highlighting

    Matches and named groups are colored as you type.

Test string

Matches highlight as you type

Match results

Sandboxed Web Worker

Type a pattern to see live matches.