Regex Tester & Cheat Sheet
Test regular expressions in real-time and access common patterns.
Flags:
/
/g
No matches found
Cheat Sheet
Regex Tester & Cheat Sheet
Free online Regex Tester and Cheat Sheet. Test your regular expressions against text in real-time. Includes a quick reference guide for common regex patterns.
1How to Use Regex Tester
- Enter your regular expression pattern.
- Add flags (g, i, m) if needed.
- Type or paste your test string.
- Matches will be highlighted instantly.
2Common Use Cases
- Validating email addresses and phone numbers.
- Extracting specific data from large text files.
- Replacing patterns in text editors or code.
3Frequently Asked Questions
What is Regex?▼
Regular Expressions (Regex) are sequences of characters that define a search pattern. They are used for string searching and manipulation.
What does the 'g' flag do?▼
The 'g' (global) flag indicates that the regex should be tested against all possible matches in a string, not just the first one.
Regex Basics
Meta Characters
.: Any single character^: Start of string$: End of string*: 0 or more+: 1 or more?: 0 or 1
Character Classes
\d: Digit [0-9]\w: Word char [a-zA-Z0-9_]\s: Whitespace[abc]: a, b, or c[^abc]: Not a, b, or c