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Regex Tester

Test regular expressions against sample text with real-time match highlighting.

Regex Tester by Utilflow. Tests regular expressions against sample text with live match highlighting. Shows all matches, capture groups, and supports common regex flags (g, i, m, s).

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Processing mode

Browser-side processing

Accepted input

Text input

Output format

On-screen output

File limit

No file upload limit

Batch limit

Single text session

Category

UUID generation, hashing, timestamps, and regex testing.

What this tool does

Tests regular expressions against sample text with live match highlighting. Shows all matches, capture groups, and supports common regex flags (g, i, m, s).

How it works

Regex is compiled and executed in real-time in your browser. No server communication.

Performance profile

Real-time matching. Complex patterns with catastrophic backtracking may freeze the UI temporarily.

Common use cases

The strongest fit for regex tester is practical, repeatable file work where teams want speed without losing clarity.

Debugging regex patterns

Testing data extraction patterns

Learning regular expression syntax

Frequently asked questions

What does Regex Tester do?

Tests regular expressions against sample text with live match highlighting. Shows all matches, capture groups, and supports common regex flags (g, i, m, s).

How does Regex Tester process files?

Regex is compiled and executed in real-time in your browser. No server communication.

Is Regex Tester private?

100% client-side. Your patterns and text never leave your browser.

What are the limits for Regex Tester?

Uses JavaScript RegExp engine — some lookbehind patterns may not work in older browsers

Ready to use regex tester inside the full workspace?

Public pages handle discovery and sharing. The private dashboard handles the actual run flow, saved activity, and your account-level workspace.

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