Quick three-step workflow
How to use the regex tester
- 1
Add the source
Enter the values, paste the text or choose the files you want to process.
- 2
Adjust the useful controls
Choose the format and options that match your intended result. Defaults are selected for common tasks.
- 3
Verify before exporting
Review the result and diagnostics, then copy or download the finished output when available.
A more useful regex tester
Debug JavaScript regular expressions against sample text. Inspect match positions and capture groups, then preview replacement output before using the pattern. Rantey keeps the core action immediate while showing enough detail to catch common mistakes before the result is used.
Private, fast and designed for mobile
The calculation or conversion happens in your current browser tab. Keeping the operation on the device avoids a round trip to an application server and helps protect source text and files. The interface uses readable labels, large touch targets and stacked controls on smaller screens.
Check the result before you use it
Automated output should still be reviewed when it affects production data, security, billing, schedules or important files. This page exposes validation messages, summaries or formulas where relevant so the result is easier to understand instead of acting like an unexplained black box.
Frequently asked questions
Regex Tester FAQ
Is Regex Tester free to use?+
Yes. The tool is free, requires no account and does not add a watermark to downloaded results.
Does this tool work on phones?+
Yes. The workspace adapts to narrow screens, uses touch-friendly controls and works in current mobile browsers.
Is my input uploaded or stored?+
No. Processing runs locally in your browser. Your input is not submitted to Rantey or saved in an account.
What makes this tool different?+
It combines the primary task with validation, useful controls and explainable output so you can verify the result before copying or downloading it.