lookupdock

Free tool

E.164 phone number formatter.

Turn a national or international phone number into the format your API expects. Check its numbering-plan format before you copy it.

Format a number

No account or credits required.

Include + and the calling code, or select a country below. Omit extensions.
Select the country the number belongs to. A number starting with + supplies its own country context.
Clear result

Sent securely to LookupDock for this result. The number is not saved to a lookup history or sent to analytics or a phone supplier.

Your result

Enter a number to see its E.164 format, country and numbering-plan checks here.

Current carrier, ownership, reachability and portability are not checked.

What is E.164 format?

E.164 writes an international phone number as +, its country calling code and the national number, with no spaces or punctuation. The number contains at most 15 digits. National dialing prefixes depend on the country; let the parser handle them instead of deleting a leading zero yourself.

Reserved fictional example numbers
InputCountry contextE.164
+1 (415) 555-0132From +1+14155550132
020 7946 0018United Kingdom (GB)+442079460018
020 7946 0018Not selectedSelect a country first

A correctly formatted number is not evidence of consent to contact its owner. Keep extensions separate; they are not part of an E.164 number.

Format reference: ITU-T E.164 (February 2026). This tool uses Phonelib's numbering-plan metadata locally, with no live carrier lookup. The examples above are covered by LookupDock's parser tests.

Fix common formatting problems

A national number needs a country

Choose where the number belongs, not where you are now. For example, 020 7946 0018 needs United Kingdom (GB). An explicit +44 overrides the country selector.

00 and 011 are not universal prefixes

International dialing prefixes depend on where a call starts. For this tool, use + followed by the country calling code when you know it, rather than assuming 00 works everywhere.

Do not delete every leading zero

The UK national dialing prefix is removed in E.164; a significant leading zero in an Italian number is retained. The numbering plan determines the result.

Keep extensions separate

Remove ext 123, x123 or ;ext=123 before formatting. Store the extension separately from the E.164 number.

Store phone numbers as text

Keep the leading + and any significant zeros. Use a string in JSON and a text column in your database or spreadsheet; phone numbers are identifiers, not quantities.

A valid range does not prove delivery

Metadata can lag new allocations. A valid result does not establish assignment, SMS support or reachability; an unknown result needs review. Confirm ownership separately when your workflow requires it.

Numbering-plan details: Google libphonenumber FAQ. Separate extension syntax: RFC 3966, section 5.3.

Checking more than one number?

Use LookupDock's phone API in your workflow, or upload a CSV to check a list. Paid workflows include numbering-plan checks; they do not establish whether a number is active.

Phone API · fixed example
curl -X POST https://lookupdock.com/api/v1/phone \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"value":"+14155550132"}'

Send value as an E.164 string, or a national number with the optional two-letter country. The API returns E.164 in data.formatted; the spaced display formats above are a free-tool feature. This fixed fictional example does not include your input. Demo mode accepts published samples without credits; live API requests use credits.

Automate phone checksClean a CSV

API and CSV: 7-day trial with 500 credits, card required. Then $99/month for 20,000 shared credits. See pricing.