Regular Expression Tester
Test JavaScript regular expressions and inspect match positions and capture groups.
//gu
Usage, example, and limits
Usage
- Enter the regular expression body without syntax that only exists in another language.
- Select the required g, i, m, or s flags.
- Use realistic but non-sensitive sample text to inspect matches and groups.
Limits
- Regex syntax and escaping differ across programming languages.
- Expressions with heavy backtracking can become very slow on particular input.
- Regex is useful for local format checks but does not replace a complete parser or business validation.
Example
- Input
Pattern: \d{4}-\d{2}-\d{2} Text: Released 2026-10-07- Output
Match: 2026-10-07
This pattern checks the shape but does not prove that a calendar date exists.
Data handling
Input and results are processed only in the current browser tab. KitOtter does not upload, store, or analyze them to complete this task.