Regex Tester
Test a regular expression against sample text with live match highlighting.
Match details
| # | Match | Index | Groups |
|---|
Replace
About the Regex Tester
Type a pattern and see every match highlighted in your test text as you type, with a table of match positions and capture groups. Flags can be toggled with buttons instead of remembering the letters.
A replace box below shows what your pattern would produce as a substitution, with $1 and $2 group references supported.
Frequently asked questions
Which regex flavour is this?
JavaScript's, which is close to PCRE for everyday patterns. Lookbehind and named groups work in modern browsers.
Why does my pattern match nothing?
The most common causes are a missing global flag, an unescaped special character such as a dot or bracket, and case sensitivity.
Related tools
All Developer →Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to text, with full Unicode support.
SQL Formatter
Format a messy SQL query into readable, indented lines.
Password Generator
Generate strong random passwords with a live strength meter.
QR Code Generator
Create a downloadable QR code for a link, text, Wi-Fi, phone number or email.
Markdown Preview
Write Markdown and see the rendered result and HTML side by side.
Image to Base64
Convert an image into a Base64 data URI for CSS, HTML or JSON embedding.