Example strings
Each line becomes a sample input for pattern generation.
Email pattern
High confidence/^[^\s@]+@[^\s@]+\.[^\s@]+$/iMatch standard email-style addresses.
Smart Regex Builder
Regex Generator Online
Use this regex generator online to create, explain, and test regular expressions from examples directly in your browser.
- Generate from examples
- Test with live match highlights
- Copy for JS, TS, or Python
Quick modeAutosaves in this browser
Quick templates
Generated pattern
Use the generated regex as-is, or move it into test mode to tweak flags and cases.
/^[^\s@]+@[^\s@]+\.[^\s@]+$/igimsu
Live results
Generate, explain, and validate the pattern in one pass.
See the regex, what it means, and which test lines pass without digging through token noise.
Active regex
/^[^\s@]+@[^\s@]+\.[^\s@]+$/i3 lines • 3 matched • 0 unmatched
Pattern summary
Email pattern • High confidence
Match standard email-style addresses.
const regex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/i;
Match results
One row per test string
Case 1
Matchedalex@example.com✔ Full line matched.
Case 2
Matchedmaya@company.io✔ Full line matched.
Case 3
Matchedtest.user@site.dev✔ Full line matched.
What this regex matches
- Matches the full line from start to end.
- Requires text before and after @.
- Ignores letter case.
- Matches all 3 current test lines.
Show detailed breakdown
^Start of string
Match from the start of the string.
[^\s@]+One or more character outside sets
Match one or more character outside sets.
@@ symbol
Match the @ character.
[^\s@]+One or more character outside sets
Match one or more character outside sets.
\.Literal .
Match the literal character ..
[^\s@]+One or more character outside sets
Match one or more character outside sets.
$End of string
Match up to the end of the string.
Why it helps
Why use an online regex generator
Generate a starter pattern from real examples instead of writing syntax from memory.
Test matches and non-matches in one place before copying a pattern into code.
Use explanations to understand inherited regex or generated expressions.
How to use it
How to generate regex online
1 Describe the pattern or provide representative sample strings.
2 Review the generated expression, live match results, and explanation.
3 Copy and adapt the regex for your programming language or validation layer.
Quick tips
Regex generator tips
Include negative examples so the generated pattern avoids false positives.
Test with messy real-world strings, not only perfect samples.
Keep patterns as specific as your use case requires, but avoid validating more than you need.
FAQ
Online regex generator questions
Can I generate regex from examples?
Yes. Add representative strings and use the generated pattern as a starting point for testing and refinement.
Can I explain an existing regex?
Yes. The builder is designed to make regex parts easier to understand before you edit or reuse them.
Can I test regex matches online?
Yes. You can test matching and failing inputs in the browser before copying the pattern.
Can I use generated regex in Python or JavaScript?
Yes. Copy the pattern and adjust delimiters, flags, or escaping for your target language.
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