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Free tool · Real numbering plans

Is that phone number
even real?

Validate against each country's actual numbering plan, get the E.164 format every API wants, and learn whether you're about to text a landline.

Validated locally with Google's libphonenumber — real per-country number plans, not a regex. Nothing leaves your browser.

Questions, answered honestly

What is E.164 and why does every tool demand it?

The international standard format: +[country code][number], no spaces, no dashes — +15550102030. It's unambiguous across every country, which is why SMS APIs, dialers and CRMs standardize on it. Store E.164, display whatever format you like.

How can a browser validate phone numbers properly?

This tool ships Google's libphonenumber rules — the same per-country numbering plans that power Android's dialer. It knows that a US number has 10 digits with specific area-code rules, that UK mobiles start with 07, and so on. It's real validation against national plans, not a length check.

Why does line type matter for outreach?

Because SMS to a landline silently disappears (or worse, gets read aloud by a robocall service), and dialing a VoIP number often means a software inbox nobody answers. Knowing mobile vs landline vs VoIP before you build a sequence saves the whole channel.

Valid means someone will answer, right?

No — valid means the number is well-formed under its country's numbering plan. Whether it's assigned, active and belongs to your prospect needs a carrier lookup (HLR), which requires a paid API. Same honesty as email: structure is checkable for free, existence isn't.

What about compliance before texting or calling?

Big topic, short version: B2C texting in the US needs prior consent under the TCPA, quiet hours apply, and every text needs opt-out language. B2B calling is looser but do-not-call lists still apply. Validation is step zero — consent is the actual gate.

One contact list. Every channel.

Norbelys is built for outreach beyond email — the same contacts, sequences and honest analytics extend to SMS and calls as channels roll out. Clean data in, every channel out.

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