Toolzie

Regex Tester

Enter a regex and test string above.

How to Use the Regex Tester

Enter regex pattern and test string. Matches highlighted real-time. Flags (g/i/m). Groups shown.

Visual feedback for regex debugging. Build patterns faster than code trial-and-error.

Frequently Asked Questions

Flavor?

JavaScript regex engine; supports lookaheads, lookbehinds, named groups, Unicode.

Groups?

Yes, numbered and named.

Flags?

g (global), i (case-insensitive), m (multiline).

Save?

Copy pattern and test string.

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About This Tool

Test and debug regular expressions in real time with the Toolzie Regex Tester. Enter your pattern and test string to see all matches highlighted instantly — with support for flags, groups, and common regex flavours.

How to Use

  1. Enter your regular expression in the pattern field.
  2. Set any flags (g for global, i for case-insensitive, m for multiline).
  3. Paste your test string in the text area.
  4. All matches are highlighted in real time — view match details and capture groups below.

Frequently Asked Questions

What regex flavour does this use?

JavaScript's built-in RegExp engine, which is compatible with most web and general-purpose regex patterns.

How do I match all occurrences?

Add the g (global) flag to find all matches instead of just the first.

How do I make my regex case-insensitive?

Add the i flag to ignore upper/lower case differences.

What is a capture group?

A group defined with parentheses (e.g. (\d+)) captures matched text separately, making it accessible via match groups.