What is E.164 format?

E.164 is the international standard for phone numbers: a leading + followed by the country code and the national number, written as digits only with no spaces, dashes, or parentheses, up to 15 digits total. Messaging APIs like Twilio, WhatsApp, and Telegram expect numbers in exactly this form.

Does my phone number leave my browser?

No. Everything runs client-side, directly in your browser. Nothing you type is sent to a server, logged, or stored — the formatting and validation happen entirely on your device.

Why do I need to pick a country?

If the number you paste already starts with a + and a country code, the tool can usually detect the country automatically. But many numbers are written in local format without a country code, so picking a country tells the tool which country code to prepend and which national numbering rules to validate against.

What does "possible but not confirmed valid" mean?

It means the number has a plausible length and structure for the selected country, but the tool cannot confirm it is an active, assigned number — that would require a live lookup against carrier databases. Treat it as a strong signal, not a guarantee, before sending SMS or WhatsApp messages.

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Built by UnifyPort

E.164 Phone Number Formatter

Normalize any phone number to E.164 and validate it — entirely in your browser.

Phone number

Default country

Used only when the number doesn't include a country code (no leading "+").

Enter a phone number to get started

Why E.164?

E.164 is the international standard for phone numbers: a leading + followed by up to 15 digits, country code first, no separators. Messaging APIs (Twilio, WhatsApp, Telegram, X DMs) all want numbers in this form, but humans rarely type them that way — they leave out the country code, use parentheses, or include leading zeros. Normalizing once on input saves you from cryptic delivery failures later.

FAQ

What is E.164 format?: E.164 is the international standard for phone numbers: a leading + followed by the country code and the national number, written as digits only with no spaces, dashes, or parentheses, up to 15 digits total. Messaging APIs like Twilio, WhatsApp, and Telegram expect numbers in exactly this form.
Does my phone number leave my browser?: No. Everything runs client-side, directly in your browser. Nothing you type is sent to a server, logged, or stored — the formatting and validation happen entirely on your device.
Why do I need to pick a country?: If the number you paste already starts with a + and a country code, the tool can usually detect the country automatically. But many numbers are written in local format without a country code, so picking a country tells the tool which country code to prepend and which national numbering rules to validate against.
What does "possible but not confirmed valid" mean?: It means the number has a plausible length and structure for the selected country, but the tool cannot confirm it is an active, assigned number — that would require a live lookup against carrier databases. Treat it as a strong signal, not a guarantee, before sending SMS or WhatsApp messages.