🧩 Regex Tester & Generator

Test regular expressions in real-time with live highlighting. Generate regex patterns from examples or choose from common patterns below.

📚 Quick Patterns:

📧 Email

^[\\w.-]+@[\\w.-]+\\.\\w+$

🌐 URL

https?://[^\\s]+

📱 Phone (US)

\$?\\d{3}\$?[-.\\s]?\\d{3}[-.\\s]?\\d{4}

📅 Date (YYYY-MM-DD)

\\d{4}-\\d{2}-\\d{2}

🖥️ IP Address

\\b(?:\\d{1,3}\\.){3}\\d{1,3}\\b

🎨 Hex Color

#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})

Regular Expression:

Flags:

g (global) i (case-insensitive) m (multiline) s (dotAll)

Test String:

📖 Quick Reference

. Any character

\\d Digit (0-9)

\\w Word character

\\s Whitespace

^ Start of string

$ End of string

* 0 or more

+ 1 or more

? 0 or 1

{n} Exactly n times

[abc] Any of a, b, or c

(abc) Capture group

❓ Frequently Asked Questions

What is a regular expression (regex)?

A regular expression is a sequence of characters that define a search pattern. They're used for pattern matching, text validation, and text manipulation.

What do the flags mean?

Flags modify how regex patterns work: g (global) finds all matches, i (case-insensitive) ignores case, m (multiline) makes ^ and $ match line breaks, s (dotAll) makes . match newlines.

How do I test email validation?

Use the Email quick pattern and test it with valid/invalid email addresses. For production, use established libraries rather than writing custom email regex.

What are capture groups?

Capture groups are parts of the pattern enclosed in parentheses ( ). They capture matched substrings that can be referenced or extracted separately.