Regex tester
Test a regular expression in a separate worker with a processing time limit.
Regex tester: inputs, results and limitations
Test a regular expression in a separate worker with a processing time limit.
How to use Regex tester
- Paste your text or use the example to inspect the operation.
- Review the options before running: Regex pattern: \d+ · Regex flags: g
- Inspect the preview or result, then download a new file.
An illustrative use case
All digit runs matched in Order 123 and 456.
Sample input
Order 123 and 456
What to inspect in the output
Use the global flag when all matches are needed. Check escaped backslashes and test a realistic input length. Pathological expressions may be stopped by the worker timeout.
Where this tool stops
Runs in a bounded worker; long-running expressions time out.
Settings and starting values
| Control | Starting value |
|---|---|
| Regex pattern | \d+ |
| Regex flags | g |
Troubleshooting Regex tester
Check source syntax and distinguish literal characters from their escaped representation. Run the example first, then compare with your failing input to isolate the invalid part.
Questions about Regex tester
Why did my regex time out?
Some expressions take excessive time on particular inputs. Simplify nested repetition and test shorter text rather than repeatedly running a stalled pattern.
What input does Regex tester need?
Use the sample text shown below, then replace it with your own input. Runs in a bounded worker; long-running expressions time out.
Which options does Regex tester provide?
Regex pattern, Regex flags. Review the starting values in the table and adjust them for your input.
Your original input is preserved. Review the new output before using it in a published page, customer delivery or production workflow.
JavaScript enables the interactive workspace.