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Regex Library
Production-ready regex patterns with copyable snippets, developer explanations, and a built-in test area.
Find a pattern
10 patterns found
Email (practical)
Validates common email formats in forms and API payload checks.
Pattern
/^[\w.+-]+@[\w-]+\.[a-zA-Z]{2,}$/gSnippet
const regex = new RegExp("^[\\w.+-]+@[\\w-]+\\.[a-zA-Z]{2,}$", "g")
const matches = input.match(regex)Test area
Edit sample text and flags to validate behavior quickly.
Flags
Sample text
Matches (1)
| # | Index | Value |
|---|---|---|
| 1 | 0 | dev@example.com |
How to use this regex library
- Pick a ready pattern from the library list.
- Copy the JavaScript snippet directly into your code.
- Validate behavior in the built-in test area before shipping.
- Adjust flags to match your runtime behavior.
Developer note
Regex can become brittle when it tries to fully parse complex grammars. Use these patterns as practical guards and extraction helpers, then follow with domain-specific validation where needed.
FAQs
What is the difference between this Regex Library and a regex tester?
A tester only checks patterns you already know. This library gives you production-ready patterns, plain-English explanations, and a test area in one place so you can discover and validate patterns faster.
Can I copy regex snippets directly into JavaScript code?
Yes. Each pattern includes a copyable snippet in JavaScript format so you can paste it into your codebase immediately.
Are these regex patterns strict RFC-level validators?
Most patterns are practical validators for day-to-day engineering use. For strict standards compliance (for example full email RFC parsing), combine regex with domain-specific validation logic.
Why does changing flags affect match results?
Regex flags change execution behavior. For example, g returns all matches, i ignores case, and m changes line-anchor behavior for ^ and $. This tool lets you test flag impact before shipping.
Does Regex Library send test text to a server?
No. Matching runs entirely in your browser, and input text is not uploaded.
Is Free Regex Library - Ready Patterns, Snippets, and Test Area free to use?
Free Regex Library - Ready Patterns, Snippets, and Test Area is completely free and runs in your browser.
Does Free Regex Library - Ready Patterns, Snippets, and Test Area send my data to a server?
No. Free Regex Library - Ready Patterns, Snippets, and Test Area processes input directly in your browser.
Do I need to create an account to use Free Regex Library - Ready Patterns, Snippets, and Test Area?
No account is required to use Free Regex Library - Ready Patterns, Snippets, and Test Area.
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