Regex Tester
Test JavaScript regular expressions and capture groups.
Your input is processed locally in your browser. It is not saved, logged, or sent with analytics.
0 chars
0 chars
Run: Ctrl/⌘ + Enter · Clear: Ctrl/⌘ + Shift + X
Matches
Enter a value to begin.
What this calculator does
Run a pattern against text locally and inspect matches, ranges, and capture groups.
Inputs and what they mean
- Regular expression
- — text value.
- Test text
- — text value.
How to use it
- Paste or enter content in the editor.
- Adjust any options for the result you need.
- Copy or download the locally processed output.
Formula
Uses the browser's JavaScript RegExp engine and reports match ranges and capture groups.
Worked example
Find capitalized words
Match capitalized words and inspect their positions.
Reading the result
The matches appears in the output box and can be copied straight out. Nothing you paste leaves your browser.
Limitations and assumptions
Results depend entirely on the figures you enter and are rounded for display. They are for general information and education, not professional advice.