Regex Tester
DeveloperProcessed Locally — 100% PrivateTest regular expressions with match highlighting.
How to Use Regex Tester Online
Test and debug Regular Expressions with real-time match highlighting, capture group extraction, and regex flag controls (g, i, m, s, u).
Input & Prepare
Enter your Regular Expression pattern and select flags.
Configure & Adjust
Paste sample test strings in the test area.
Export or Copy
View instant highlights, match counts, and capture groups.
Common Use Cases
- Validate email, phone number, and postal code regex patterns
- Extract URLs, IP addresses, and log components from system output
- Test complex text replacement expressions before deploying code
Technical Specifications & Limitations
Uses the native JavaScript RegExp engine (V8 / JavaScriptCore).
Frequently Asked Questions
Does this support named capture groups?
Yes, standard ECMAScript named capture groups `(?<name>...)` are fully supported.
100% Client-Side Privacy Guarantee
DailyToolbox processes all operations using local WebAssembly and Web APIs inside your browser memory. No data, files, or sensitive inputs are ever uploaded to an external server or saved in tracking cookies.
Related Keywords
Related Developer Tools
Explore all Dev toolsJSON Formatter
Format, validate and minify JSON with error hints.
Base64 Encode/Decode
Encode and decode Base64 text instantly.
URL Encode/Decode
Encode or decode URL components.
JWT Decoder
Inspect JWT header and payload — client-side only.
Hash Generator
SHA-1, SHA-256, SHA-384, SHA-512 via SubtleCrypto.
UUID Generator
Generate v4 UUIDs in bulk.