Tool guide / 工具说明
Regex Tester for fast browser-based work
Test regular expressions, highlight matches, and copy match lists.
中文：测试正则表达式，高亮匹配内容并复制匹配列表。
Example: Validate extraction patterns for emails, IDs, log lines, filenames, and routes.
Practical workflows
Where this tool fits in real work
Use cases
- Test extraction patterns for emails, IDs, log lines, filenames, and route segments.
- Review match positions and captured text before using a pattern in code.
- Copy a match list for quick QA notes or documentation examples.
Review notes
- The tool uses the browser JavaScript RegExp engine, so server-side engines may differ.
- Test against negative examples, not only the examples you expect to match.
Local-first handling
This page is built as a browser utility. Inputs are processed in the page where possible, with no account requirement and no intentional upload step for the tool workflow.
Use with judgment
When to use Regex Tester
Good fit
- Test extraction patterns for emails, IDs, log lines, filenames, and route segments.
- Review match positions and captured text before using a pattern in code.
- Copy a match list for quick QA notes or documentation examples.
Before copying results
- The tool uses the browser JavaScript RegExp engine, so server-side engines may differ.
- Test against negative examples, not only the examples you expect to match.
Use a stricter workflow
If the content includes production secrets, live tokens, or customer system credentials, do not treat it as a casual debugging snippet.
Related guides
Keep learning this workflow
Why local-first browser tools matterDecide which tasks belong in browser-local tools.
Regex Tester in the BrowserTest JavaScript regular expressions with sample text before using them in code or documentation.
Private Online Tools: What to CheckA practical checklist for choosing browser tools when privacy, speed, and trust matter.
Related tools
Keep working with nearby utilities
FAQ
Regex Tester questions
Which regex engine is used?
The browser JavaScript RegExp engine.
Can I see match positions?
Yes. The match list includes indexes.
Is this tool free?
Yes. The current Toolkits tools are free to use and do not require an account. If advertising is added later, it should be clearly labeled and kept away from primary tool controls.