Free Regex Tester & Matcher Online

Test, build, and debug regular expressions (Regex) instantly against live text. Perfect for developers.

Regular Expression

//g

Test String

Hello World! This is a Test string for Regex checking.

Match Results

5 Matches
Match 1Index: 0
Hello
Match 2Index: 6
World
Match 3Index: 13
This
Match 4Index: 23
Test
Match 5Index: 39
Regex

How to Use

1

Type your regular expression pattern in the top input box (without the enclosing slashes).

2

Toggle the regex flags (g for Global, i for Case Insensitive, m for Multiline).

3

Type or paste the text you want to test against in the Test String area.

4

Matches will be instantly highlighted in blue within the text.

5

View the exact matches and capture groups below the text box.

Features

Real-time regex evaluation and visual highlighting
Supports standard JavaScript (ECMAScript) regex engine
Interactive flag toggling (g, i, m, s, u)
Displays detailed match arrays and capture groups
100% secure client-side execution — your data stays private

FAQ

Are you struggling to write the perfect regular expression for form validation, text parsing, or data scraping? Our free online Regex Tester is the ultimate tool for JavaScript and backend developers in 2026. Build, test, and debug your regex patterns in real-time. Instantly see which parts of your test string match your pattern with clear visual highlighting. Toggle flags like global (g) and case-insensitive (i) with a single click to see how they affect your capture groups. Because the matching engine runs entirely client-side, you can safely test regex patterns against sensitive PII data or secure logs without worrying about server-side tracking or data breaches.

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