E.164
International telephone numbering standard that ensures globally unique phone numbers
What is E.164?
E.164 is an international numbering standard defined by the ITU-T that specifies the format for telephone numbers worldwide. An E.164 number includes a country code, area code, and subscriber number, with a maximum of 15 digits (e.g., +1 212 555 1234).
E.164 in VoIP
VoIP systems and SIP endpoints typically use E.164 formatted numbers for call routing. Consistent use of E.164 ensures interoperability between different carriers, PBX systems, and softphone clients across borders.
