Example strings
Each line becomes a sample input for pattern generation.
Email pattern
High confidence/^[^\s@]+@[^\s@]+\.[^\s@]+$/iMatch standard email-style addresses.
Smart Regex Builder
Regex for Phone Number Validation
Generate and test regex for phone number validation — US formats, international E.164 numbers, and separator styles — in a browser-based regex builder.
- Generate from examples
- Test with live match highlights
- Copy for JS, TS, or Python
Quick modeAutosaves in this browser
Quick templates
Generated pattern
Use the generated regex as-is, or move it into test mode to tweak flags and cases.
/^[^\s@]+@[^\s@]+\.[^\s@]+$/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.
$End of string
Match up to the end of the string.
Why it helps
Why generate phone number regex with a builder
Handle common phone formats like (555) 123-4567, 555-123-4567, and +14155551234 without hand-writing every variation.
Test matching and failing samples so the pattern accepts real numbers and rejects malformed ones.
Read a plain-English explanation of each token so the validation rule stays maintainable.
How to use it
How to build a phone number regex
1 Paste phone numbers that should match — include every format your form accepts.
2 Add malformed samples that should fail, then review the generated pattern and explanation.
3 Copy the regex into JavaScript, Python, or backend validation code.
Quick tips
Phone number regex tips
A permissive baseline like ^\+?[\d\s().-]{7,20}$ catches most real-world input; tighten it per country only if you must.
For international numbers, validate the E.164 shape ^\+[1-9]\d{1,14}$ and let a phone library handle country rules.
Normalize input (strip spaces, dots, and dashes) before validating to keep the pattern simple.
FAQ
Phone number regex questions
Can this generate regex for US phone numbers?
Yes. Add samples like (555) 123-4567 and 555-123-4567 and the builder generates a pattern you can test against matching and failing cases.
Can I validate international phone numbers with regex?
Yes, for shape checks. The E.164 pattern ^\+[1-9]\d{1,14}$ validates international number structure; carrier-level validity needs a phone library or verification step.
Should regex be my only phone validation?
No. Use regex to catch obvious format errors early, then rely on SMS or call verification to prove a number is real and reachable.
Can I test the phone regex before copying it?
Yes. The regex builder shows live match results for both valid and invalid samples before you copy the pattern.
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