Glossary
Phone data, defined
A plain-English reference for the terms behind phone-number intelligence. Each entry links to the APIs and guides that put it to work.
- Carrier
- The network operator that currently provides service for a phone number.
- Disposable number
- A temporary phone number, usually VoIP, issued to receive a single verification code and then discarded.
- E.164
- The international standard format for phone numbers: a plus sign, country code, and up to 15 digits.
- HLR (Home Location Register)
- The carrier database of mobile subscribers that an HLR lookup queries to check a number's live status.
- Landline
- A fixed, voice-only phone line that cannot receive SMS.
- Line type
- The category of a phone line — mobile, landline, VoIP, or toll-free — which determines how you can contact it and how risky it is.
- Liveliness
- A bundle of real-time signals describing whether a phone number is active, reachable, and safe to use right now.
- MCC / MNC
- Numeric codes identifying a mobile number's country (MCC) and network operator (MNC).
- MSISDN
- The full international mobile number that maps to a SIM — effectively the dialable number in E.164 form.
- OTP (One-Time Passcode)
- A short code sent to a phone to verify ownership — and a common target for disposable-number and pumping fraud.
- Ported number
- A number that has moved to a different carrier while keeping its original digits, breaking range-based carrier lookups.
- Reachability
- Whether a live number can actually receive a call or SMS at this moment, versus being switched off or out of service.
- Toll-free number
- A business number where the called party pays for the call — useful for support routing, not personal outreach.
- VoIP (Voice over IP)
- A phone line that routes calls over the internet rather than traditional telephone infrastructure.
Want the deep dives?
The guides put these concepts to work with practical, step-by-step advice.