Phone Number Format Validator

What is E.164 format?

E.164 is the international telephone numbering plan defined by the International Telecommunication Union (ITU). It guarantees that every phone number in the world has a unique, unambiguous representation that any network or software can route correctly.

An E.164-formatted number always:

• Begins with a + sign
• Is followed by the country calling code (1 to 3 digits)
• Continues with the national subscriber number
• Never exceeds 15 digits total
• Contains no spaces, dashes or parentheses

Examples by country

• USA / Canada: +14155552671
• France mobile: +33612345678
• UK mobile: +447911123456
• Germany: +4915123456789
• Spain: +34612345678
• Italy: +393331234567
• Australia: +61412345678

When do you need to validate phone numbers?

• SMS marketing & Twilio — APIs reject non-E.164 numbers
• WhatsApp Business — only E.164 numbers can be added
• CRM imports — clean lists prevent failed campaigns
• OTP authentication — providers charge per failed delivery
• Lead qualification — invalid numbers waste sales time

Privacy notice

This tool runs entirely in your browser. Numbers you type are never sent to our servers and never logged. If you'd like to find the owner of a number (name, location, social profiles), use our reverse phone lookup — that's a separate paid service.