Free phone number validator
Paste any phone number in any format. This checks it against the official national numbering plan for its country, not against a generic length rule, and tells you exactly why it passed or failed.
Free, no signup, no daily limit. We do not store what you check here.
What "valid" actually means here
A number can fail in three different ways, and most validators only catch the first. It can be the wrong length for its country code. It can be the right length but sit in a prefix the regulator never allocated. Or it can be perfectly allocated and simply not in service. This tool answers the first two offline and for free. The third needs a live carrier query, which is what the paid API adds.
Why format checks are not enough
An independent 2026 benchmark measured popular validation APIs between 68% and 76% accuracy. The misses were rarely exotic: they were structurally perfect numbers that could never ring anyone. Regulators in every major market reserve blocks for film and training use, and a length-and-prefix check waves all of them through.
Questions
Is this really free?
Yes, with no signup and no daily quota. It runs on offline numbering-plan data, so it costs us nothing to serve.
Does it tell me if the number is switched on?
No. Reachability requires querying the carrier network in real time. This tool answers whether the number is structurally valid and allocated.
What format should I use?
Anything. International format with a plus is most reliable, but spaces, dashes and brackets are all handled.
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E.164 phone number formatter
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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.