# Regex Tester

> Test regular expressions against sample text and see every match with its capture groups.

To test a regular expression, enter your pattern and sample text. Every match is listed with its position and all capture groups, including named groups. Patterns use JavaScript regex syntax, so what works here works in Node and the browser.

**URL:** https://convertto.tech/t/regex-tester
**Category:** Developer Tools (https://convertto.tech/c/developer-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Enter or paste your pattern.
2. Choose the flags.
3. Enter or paste your test text.
4. The result appears immediately — copy or download it.

## FAQ

### Which regex flavour is this?

JavaScript (ECMAScript). It differs from PCRE in a few places — no atomic groups or possessive quantifiers, and lookbehind support depends on the browser engine.

### Why does my pattern match nothing?

The most common cause is unescaped special characters. A literal dot must be written as \. and a literal slash inside a character class needs escaping too.

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