RegEx Cheat Sheet
Anchors
^Start of string$End of string\bWord boundaryQuantifiers
*0 or more times+1 or more times?0 or 1 time{n,m}Range (min, max)Character Classes
\dDigit (0-9)\wWord (a-z, 0-9, _)\sWhitespace.Any characterGroups & Logic
(...)Capture group[...]Character set(?:...)Non-capturing|Alternation (OR)RegEx Tester & Master
Professional RegEx Workstation
RegEx Cheat Sheet
Instant access to a professional reference guide covering anchors, quantifiers, classes, and groups directly in your workstation.
Live Highlighting
Instantly see matches in your test string as you type your regex or modify the text.
Technical Precision
Detailed pattern testing with support for advanced JavaScript RegExp features and real-time validation.
Secure & Local
Your patterns and test data never leave your browser. Perfect for debugging sensitive strings locally.
How to Use RegEx Tester?
1. Enter Pattern
Type your regular expression in the top input field. Do not include the starting and ending slashes.
2. Set Flags
Select the desired flags like 'Global' or 'Case Insensitive' to refine your search behavior.
3. Input Test Text
Paste or type the text you want to test against. Matches will be highlighted automatically.
4. Reference Cheat Sheet
Refer to the permanent cheat sheet below to quickly find the right syntax for your regular expression.
Why Use LocalUsta RegEx Tester?
Regular expressions can be cryptic. Our tool not only tests your patterns in real-time but also provides a comprehensive cheat sheet to help you master every syntax rule instantly. 100% private and client-side.
Frequently Asked Questions
Everything you need to know about the LocalUsta Tools platform.
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