Your Interactive Regex Playground

Paste a pattern, see matches instantly, and learn by doing. Built for beginner developers and non-programmers who need to test regular expressions without installing anything.

Results update live as you type — no button needed. The Example button fills a sample input.

Why use Regex Starter?

Live matching: see results update as you type your pattern and test text

Plain-English explanations: understand what each part of your regex does

Beginner-friendly: no setup, no coding environment required

Supports flags: test global, case-insensitive, multiline, and more

Instant feedback: perfect for learning regex through experimentation

FAQ

What is a regular expression?

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

Do I need to know programming to use this tool?

No! This tool is designed for beginners. You can experiment with patterns and see immediate results, making it easy to learn regex by doing.

What do the flags like 'g' and 'i' mean?

Flags modify how the pattern is matched. 'g' means global (find all matches), 'i' means case-insensitive, and 'm' means multiline. You can combine them.

Can I test multiple patterns at once?

Currently, you test one pattern at a time. This keeps the interface simple and focused for learning.

Example input

Try it with this sample — paste it into the box above:

{"pattern": "\\b\\w+@\\w+\\.\\w{2,}\\b", "text": "Contact us at support@example.com or sales@test.org for help.", "flags": "g"}

How to use Regex Starter

  1. Enter or paste your data into the Regex Pattern & Test Text box above.
  2. The result appears instantly in the Match Results box — everything runs in your browser, nothing is uploaded.
  3. Use Copy or Download to keep the result, or Example to load a sample first.

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