Test regular expressions with live matching, highlighted results, and capture group extraction — ideal for validation and parsing
Enter a regex pattern and test text to see matches
Regex Tester helps you build, test, and debug regular expressions against real text with immediate feedback. Regular expressions are used for input validation, parsing logs, extracting IDs, cleaning text, and search/replace automation. This tool shows highlighted matches, supports common flags, and displays captured groups so you can confirm exactly what your pattern is matching (and what it isn't). Use it when a regex fails in production, matches too much, or behaves differently than expected.
Enter your regex pattern (and flags, if applicable)
Paste the text you want to test against
Run "Test Regex" to see matches and groups
Adjust the pattern until matching is correct
Copy the working pattern into your codebase or editor
Validate emails, usernames, slugs, IDs, and passwords with regex
Extract values from logs (request IDs, timestamps, IPs, errors)
Parse URLs and query parameters
Build safe search-and-replace rules for editors and scripts
Debug regex edge cases like multiline input or greedy matching
Create capture groups for replacements and transformations
Live match feedback with highlighted output
Capture group extraction for each match
Supports common regex flags (g, i, m)
Works great for JavaScript/TypeScript regex workflows
Fast local processing (no uploads)