Text & String

Regex Tester

Test and debug regular expressions

Regular Expression

//g

Presets:

Test String

Replace

Quick Reference

Character Classes

. - any character

\d - digit

\w - word char

\s - whitespace

[abc] - a, b, or c

Quantifiers

* - 0 or more

+ - 1 or more

? - 0 or 1

{n} - exactly n

{n,m} - n to m

Anchors

^ - start

$ - end

\b - word boundary

Groups

(abc) - capture

(?:abc) - non-capture

a|b - or

What is Regex Tester?

Test and debug regular expressions

Regex Tester is a free online tool that works directly in your browser. No installation or signup required. All processing happens locally on your device, ensuring your data stays private and secure.

Why Use Regex Tester?

✓100% Free - No hidden costs or premium features
✓No Signup Required - Start using instantly without creating an account
✓Privacy First - All processing happens in your browser. Your data never leaves your device
✓Lightning Fast - Instant results with no server delays

How to Use

Enter or paste your text in the input area above
The tool will automatically process your input
Copy the result or download it as a file

Features

✓Real-time pattern matching
✓Flag toggles (g, i, m, s, u)
✓Capture group display
✓Common regex presets
✓Pattern explanation

Frequently Asked Questions

What is a regular expression?

A regular expression (regex) is a sequence of characters that defines a search pattern. It is used for pattern matching, text validation, and string manipulation.

What regex flags are supported?

We support all JavaScript regex flags: g (global), i (case-insensitive), m (multiline), s (dotAll), and u (unicode).