Bulk phone number formatter
Paste a messy list. Get every number in E.164 format, duplicates removed and bad formats flagged. Runs in your browser; nothing is uploaded.
Why format before you import
The same number can arrive as (415) 555-2671, 415.555.2671 and +1 415 555 2671 from three different lead sources. To a CRM or dialer those are three different contacts, so the same person gets called or texted more than once. Converting everything to one format first lets you dedupe properly.
E.164 is the format most dialers, CRMs and SMS platforms accept on import, so a list in E.164 usually imports without rejected rows.
What formatting can't tell you
A number can be perfectly formatted and still be dead, a landline or VoIP. Those only show up with a live carrier lookup.
Upload a CSV. Get back every number marked valid or dead, mobile, landline or VoIP, with carrier.
Start 7-day free trial →See bulk phone number validation, the phone list cleaning guide, or estimate what bad numbers cost with the list health calculator.
Questions
What is E.164 format?
E.164 is the international numbering standard from the ITU. A number is written as a plus sign, the country code and the national number with no spaces or punctuation, up to 15 digits in total. A US number looks like +14155552671. Most dialers, CRMs and SMS platforms expect it.
Are my numbers uploaded anywhere?
No. The formatter runs in your browser. The numbers you paste are not sent to TrueSearch or anyone else, and nothing is stored after you close the page.
What counts as an invalid format?
For US and Canadian numbers: the wrong number of digits, an area code or exchange starting with 0 or 1, an N11 service code such as 411 in the area code position, or a 555-0100 to 555-0199 number, which is reserved for fictional use. For other countries it only checks for a country code and 8 to 15 digits.
Does a formatted number mean it works?
No. Formatting only checks the structure. A perfectly formatted number can be disconnected, reassigned, a landline that cannot receive texts, or a VoIP line. Finding that out needs a live carrier lookup, which is what TrueSearch for Business does.
How are duplicates detected?
After every number is converted to E.164, any repeat of a number already seen is marked as a duplicate. That catches the same number written different ways, such as (415) 555-2671 and +1 415.555.2671.
This guide is general information, not legal advice. TrueSearch for Business checks validity, line type and carrier from licensed telecom data. It does not check the National Do Not Call Registry, state DNC lists or the FCC Reassigned Numbers Database. Not a consumer reporting agency; not for FCRA purposes.