Regex Tester | DevZen

Global (g)Case Insensitive (i)Multiline (m)

Hello! Please reach out to our team at support@devzen.io or sales@company.com for inquiries. We also have a legacy support email: help-desk.v2@old-domain.co.uk. For billing, contact billing@payments-gateway.net. Invalid emails like support@.com or @company.com should not match.

No matches found in test string.

About Regex Tester

Overview

The Regular Expression (Regex) Tester offers a live sandbox to write, validate, and debug regex patterns against sample text strings. It highlights matches and highlights captured groups in real-time, helping developers refine their validation formulas.

🔒 Privacy & Security Guarantee

Regular expression matching runs natively inside your local tab. We do not store your testing inputs or pattern queries, allowing you to debug email matching, phone validations, or code patterns securely.

Frequently Asked Questions

What are the common regex flags?+

The 'g' flag stands for global match (finds all occurrences), 'i' stands for case-insensitive, and 'm' stands for multiline search (anchors ^ and $ match line starts/ends).

Why does my browser hang on some regex patterns?+

This is due to catastrophic backtracking. If you nest quantifiers (like (a+)+), the matching engine will evaluate combinations exponentially on non-matching inputs. Keep patterns flat to avoid this.