Regex Tester & Matcher

Test, validate, and debug regular expressions with real-time pattern matching.

Sample Presets:

Regular Expression PatternFlags: /g/

Target Test String

96 chars1 lines

1
Contact engineering at support@devrian.in or sales@devrian.com for zero-latency developer tools.
Contact engineering at support@devrian.in or sales@devrian.com for zero-latency developer tools.

Match Results2 matches

Local RegExp Engine

#1pos 23..41 (18 chars)

support@devrian.in

#2pos 45..62 (17 chars)

sales@devrian.com

✓ Valid ECMA-262 Regular Expression

2 MatchesFlags: /g/

Pattern Validation & String Inspection Workflow

Test regular expressions, validate format compliance, and parse payloads.

Step 01Active Step

Test Regular Expression

Test patterns against sample text with real-time match highlighting (ECMA-262).

Step 02

Validate UUID Strings

Test UUID pattern matching against generated UUID v4/v7 strings.

Open UUID v4 / v7 Generator

Step 03

Extract & Format JSON

Format regex-matched JSON strings into structured objects.

Open JSON Formatter & Validator

Developer Documentation & Guidance

Practical developer scenarios, best practices, and common mistakes to avoid.

When Should I Use This Tool?

•Testing regular expression patterns against sample inputs before backend deployment.
•Extracting capture groups from complex string formats (log lines, headers, URLs).
•Validating user input formatting (emails, phone numbers, UUIDs, IP addresses).

Developer Best Practices

✓Keep regular expression patterns simple and test thoroughly against edge case inputs.
✓Use named capture groups (?<name>...) for self-documenting maintainable code.
✓Be mindful of performance; avoid nested quantifiers that trigger catastrophic backtracking.

Common Developer Mistakes

!Creating patterns subject to catastrophic backtracking (ReDoS attacks).
!Forgetting multi-line (m) or global (g) flags during string matching.
!Using client-side regex as the sole validation mechanism without server verification.

Keyboard Shortcuts Help

Evaluate PatternCtrl + Enter

Copy All MatchesCtrl + Shift + C

Load PresetsAlt + 1 / 2 / 3 / 4