Learn regex by playing

Master patterns.
Capture what matters.

RegexArena turns regular expressions into short, progressive challenges. Learn by doing, get instant feedback, and improve with every match.

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Can you match only the valid emails? Most people miss it on their first try. Level 1 takes only 40 seconds.
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LIVE DEMO
Mission 17 · emails
Preparing expression…0%
Testing against examples waiting
contato@regexarena.com✓ Match
usuario123@gmail.com✓ Match
ola.mundo+news@exemplo.co✓ Match
email_invalido@× Rejected
@semusuario.com× Rejected
texto@dominio× Rejected
Instant feedbackSee the result update in real time.

What you get in RegexArena

20+
progressive levels
5
worlds
3
hint levels
100%
free
Learn by doing

A simple flow to truly understand regex.

You get an objective, write the pattern, and instantly see what you matched correctly, what you missed, and what you captured by mistake.

01

Clear missions

Each level makes it clear which values should match and which should be rejected.

02

Errors that teach

Feedback shows false positives and missed targets without interrupting the experience.

03

Real developer cases

After the basics, practice formats such as email, phone numbers, IDs, URLs, and logs.

Your first mission takes less than a minute

Stop memorizing regex. Make your first one work.

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