Data checks

Phone number check

Normalise a number to the international E.164 format, detect the country by its calling code and validate the length. Everything runs in your browser, free and no sign-up.

No sign-upProcessed locallyFree forever
E.164Runs in your browser

Results update as you type.

Used only when the number has no + or 00; the leading 0 is dropped.

Try an example

Enter a number in international format

Need carrier, line type and spam-risk? That is the paid Phone Intelligence powered by Astrina.

Nothing you enter is sent to our server. We only count anonymous usage — which tool was used, never what you typed.

How it works

What you get

01

E.164 format

The number is normalised to the international form: a plus, the country code and the national number with no separators.

02

Country by code

We detect the country from the calling code — from single-digit to three-digit prefixes.

03

Length validity

We check that the total number of digits fits the E.164 standard (from 8 to 15).

Frequently asked questions

FAQ

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What does this tool check?

The number's format: it normalises to E.164, detects the country by its calling code and checks the length. All of this runs in your browser.

Does it show carrier and spam risk?

No. Carrier, line type and spam-risk score come from the paid Phone Intelligence service powered by Astrina. Here we check only format, country code and length.

What is E.164 format?

The international standard for writing a number: a plus sign, the country code and the national number with no spaces, up to 15 digits. For example, +447700900123.

Is it free and private?

Yes. Free, no sign-up and entirely in the browser — the number is never sent anywhere.

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