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Regex for username validation in JavaScript

Q: What is the regex for username validation in JavaScript?

^[A-Za-z0-9_]{3,16}$ — A typical username is 3-16 characters of letters, digits, and underscores. This anchored pattern enforces that. Adjust the length bounds with the live tester.

A typical username is 3-16 characters of letters, digits, and underscores. This anchored pattern enforces that. Adjust the length bounds with the live tester.

Working example

/^[A-Za-z0-9_]{3,16}$/

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Describe what to match

/^[A-Za-z0-9_]{3,16}$/valid ✓

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