Regex Performance Tester for Backtracking Risk
Check regex patterns for potential catastrophic backtracking issues.
Regex Performance Tester
Evaluate regex patterns for signs of catastrophic backtracking before they hit production. Security and platform teams use this to avoid performance spikes caused by risky expressions.
How to use the Regex Performance Tester
- Paste the regex pattern.
- Click Analyze.
- Review the risk indicator.
Common use cases
- Auditing user-supplied regex patterns.
- Reviewing patterns used in validation rules.
- Hardening log parsing pipelines.
- Preventing regex-based denial of service.
Tips & notes
- Prefer specific quantifiers over nested repetition.
- Test against worst-case input examples.
- Use atomic groups or possessive quantifiers where supported.
Related developer tools
- Regex Tester
- JSON Formatter
- SQL Minifier
FAQ
Is it exact?
It uses heuristics to flag risk and may be conservative.
Does it fix the regex?
No. It only reports potential risk.
Why does backtracking matter?
Certain inputs can make a regex take excessive time to evaluate.