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Each level makes it clear which values should match and which should be rejected.
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Master patterns.
Master patterns.
Capture what matters.
RegexArena turns regular expressions into short, progressive challenges. Learn by doing, get instant feedback, and improve with every match.
Can you match only the valid emails? Most people miss it on their first try. Level 1 takes only 40 seconds.No sign-upProgress savedMobile first
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Mission 17 · emails
Preparing expression…0%
Testing against examples
waiting
contato@regexarena.com✓ Matchusuario123@gmail.com✓ Matchola.mundo+news@exemplo.co✓ Matchemail_invalido@× Rejected@semusuario.com× Rejectedtexto@dominio× RejectedWhat you get in RegexArena
24
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.
Errors that teach
Feedback shows false positives and missed targets without interrupting the experience.
Real developer cases
After the basics, practice formats such as email, phone numbers, IDs, URLs, and logs.
Popular Regex paths
Learn, test, and practice the patterns developers use.
Start with a focused guide, then test the expression and turn it into practice.
JavaScript Regex
RegExp, examples, groups, extraction, match, replace, and flags.
View guide →Regex Exercises
18 practice problems with solutions from beginner to advanced.
Try exercises →Regex for Numbers
Digits, integers, signed values, decimals, and formatted numbers.
View patterns →Regex Tester
Test patterns online and visualize matches and capture groups.
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Your first mission takes less than a minute
Stop memorizing regex. Make your first one work.
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