Telecom databases
SIP cause codes
82 SIP response codes with explanations
Q.850 cause codes
50+ ISDN/VoIP disconnect reason codes
World countries
Dialing codes + ISO 3166 details
Emergency numbers
Police, ambulance & fire by country
ISO 3166-2 codes
Subdivisions for APIs & forms
MCC/MNC database
580+ mobile operators worldwide
SMPP error codes
100 SMPP codes + DLR status
Numbering plans
National numbering plans and prefixes
Postal / ZIP codes
Worldwide postal and ZIP lookup
Guides & tutorials
SIP call flow
Animated SIP message diagrams
History of SIP
How SIP became the VoIP standard
Asterisk guide
PBX setup, dialplan, and trunks
Vicidial guide
Contact center installation & ops
Online tools
Full list in the Tools menu — DNS, IBAN, cron, hashes, and more.
My IP address
Detect your public IP, location, ISP
QR code generator
Generate QR for URL, text, WiFi, email
DNS lookup
Query A, MX, NS, TXT records
WHOIS lookup
Domain registration details
Password generator
Strong random passwords
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Our databases are regularly updated to reflect the latest ITU assignments, new codes, and protocol changes.
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