Telecom Databases
SIP Cause Codes
82 SIP response codes with explanations
Q.850 Cause Codes
50+ ISDN/VoIP disconnect reason codes
Country Dialing Codes
240+ international calling codes
MCC/MNC Database
580+ mobile operators worldwide
SMPP Error Codes
100 SMPP codes + DLR status
SIP Call Flow
Animated SIP message diagrams
Online Tools
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
Why Telecom Professionals Use ESROT
Instant Access
No signups, no paywalls. All telecom reference data is freely accessible to everyone, always.
Always Updated
Our databases are regularly updated to reflect the latest ITU assignments, new codes, and protocol changes.
Instant Search
Filter by category, country, provider, or status code range. Fully responsive, fast loading pages.
Mobile Friendly
Look up codes and references from your phone in the field. Fully responsive, fast loading pages.