Reserved and fake phone number checker
Every telecom regulator reserves blocks of numbers that look completely normal but can never belong to a real subscriber. They exist so films, adverts and training material can show a number without ringing a stranger. Format validators pass all of them.
Free, no signup, no daily limit. We do not store what you check here.
Which blocks are reserved
In the UK, Ofcom holds 07700 900xxx for mobiles and 01632 960xxx for landlines. In North America, NANPA reserves 555-0100 through 555-0199 in every area code. Australia sets aside 0491 570 xxx. Germany, Sweden, the Netherlands and France all maintain equivalents. Each range is syntactically indistinguishable from a real number.
Why these appear in your database
Two ways, mostly. Someone tested your signup form with a number they saw in a tutorial, or someone deliberately entered a plausible-looking fake to get past a required field. Both look like clean data until you try to reach them, and both are caught instantly by a lookup table.
Questions
Will other validators catch these?
Usually not. The numbers are structurally correct, so anything checking only length and prefix will report them as valid.
Are these the same as premium-rate numbers?
No. Premium-rate numbers are real and chargeable. Reserved ranges are permanently unallocated by the regulator.
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When you need more than a free tool
This page answers what can be determined offline and from public DNS. The API adds live carrier and mailbox verification, a calibrated confidence score, and the full evidence trail behind every verdict.
Credits never expire. Inconclusive verdicts are never billed. Cancel in one call. See pricing or read the docs.