DUL Data Utility Labs

Regex - Private browser tool

Regex Tester

Test regex patterns against sample text locally and inspect matches, groups, and indexes.

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Regex Tester

Private, browser-based, free to use.

What this tool helps you do

Test regex patterns against sample text locally and inspect matches, groups, and indexes. Paste your data, run the tool, copy the result, and move on. The core workflow stays on one focused page.

Best use cases

  • Convert or clean data before importing it into spreadsheets, BI tools, databases, or internal apps.
  • Debug API payloads, logs, tokens, encodings, regular expressions, and text transformations.
  • Create lightweight examples for documentation, tests, tutorials, customer support, and team handoffs.

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Regex Tester FAQ

Which JavaScript flags are supported?

Use the flags input for g, i, m, s, u, and y.

Does it show match positions?

Yes. Output includes matched text and index.

Can I test generated regex?

Yes. Paste any pattern from the Regex Generator page.