Regex Benchmark

Regex Performance Benchmarking Tool

This tool helps you:

• Compare multiple regex patterns to find the fastest one
• Identify performance bottlenecks in your regular expressions
• Detect degenerate cases that cause catastrophic backtracking
• Get optimization recommendations for better performance

Features

• Accurate timing with warmup phase for JIT optimization
• Statistical analysis (avg, min, max, median)
• Performance tier classification (fast/medium/slow/very-slow)
• Automatic detection of common anti-patterns
• Degenerate case testing for edge cases

Usage

1. Enter multiple regex patterns (one per line)
2. Provide test input strings (one per line)
3. Set iterations and warmup runs
4. Choose regex flags (e.g., 'gi', 'm')
5. Run benchmark to compare performance

Performance Tips

• Use non-capturing groups (?:...) instead of capturing groups
• Avoid nested quantifiers like (.*)+
• Use atomic groups (?>...) or possessive quantifiers to prevent backtracking
• Be specific with character classes instead of .\*
• Anchor patterns with ^ and $ when possible