Test regex patterns against text with match and group details.
Check supported input/output details and follow the tool steps before exporting.
Use these specs to validate workflow fit, privacy boundaries, and output expectations before you run regex-tester.
Cost
Free workflow with no signup gate for core usage.
Security
Processing runs in-browser where possible to reduce server upload exposure.
Device
Supports modern desktop and mobile browsers.
Tech specs
Input: regex pattern, flags, and test text. Output: highlighted matches, capture groups, positions, and summary stats.
Check supported input/output details and follow the tool steps before exporting.
01
Enter a regex pattern and choose the flags you need.
02
Paste the test string into the input panel.
03
Review highlighted matches and the per-match group breakdown.
04
Adjust the pattern or flags until the output matches the expected behavior.
Understand how to test regex online, why it matters in repeat workflows, and when to use this tool with confidence.
Test regular expressions with live match highlights, capture group details, and quick flag toggles in a private browser workspace. That makes it a practical fit when you need debug validation patterns before they reach production code, inspect capture groups for parsing and extraction work, and test case-insensitive, multiline, or unicode matching behavior.
Instead of switching between separate utilities, the current workflow keeps the main task, supporting controls, and export actions together so you can validate the result before moving on.
Enter a regex pattern and choose the flags you need. Paste the test string into the input panel. Review highlighted matches and the per-match group breakdown. Adjust the pattern or flags until the output matches the expected behavior. The goal is to keep the path from input to verified output short enough for quick tasks while still exposing the controls that matter when the data is more sensitive or more complex.
Highlights matches directly inside the sample text. Lists capture groups and match positions for deeper debugging. Makes common regex flags easy to toggle on and off. Keeps test strings private in the browser. That combination makes the tool useful for both one-off fixes and repeat operational work, especially when you want to keep the workflow inside the browser.
People often land on this page looking for test regex online, regex groups viewer, or regex flag tester. The reason the tool holds up in practice is that the copy matches the real implementation instead of promising features the interface does not support.
When the visible content stays aligned with the shipped behavior, the page is easier to trust, easier to localize, and easier to reuse as the tool evolves.
Have more questions? Reach out via our contact page and we will respond within 24 hours.
No. Regex execution runs in your browser.
The workspace supports common browser flags such as g, i, m, s, and u.
Yes. Each match lists any captured groups and where the match occurred.
Yes. Matches are highlighted directly in the sample text area for faster review.
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Regex input
Match details
Enter a test string to see matches highlighted
