How-to guidesUpdated 5/13/2026

How to validate phone numbers in bulk before importing into a dialer

Phone numbers in a CSV are usually a mess — different formats per country, missing country codes, inconsistent spacing, mix of mobile/landline/VOIP. Before importing into a dialer or SMS platform you need one clean E.164 column and ideally the type.

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What the validator returns

Pure logic, no network call — runs as fast as the CSV reads.

valid: true/false
formatted_e164: +31 6 12345678 canonical
formatted_national: human-readable national
country: ISO-2 code detected
type: mobile / landline / voip / fixed-line-or-mobile / unknown

Why "mobile vs landline" matters

SMS campaigns only work on mobile. Cold-call dialers care about VOIP detection (low pickup rates). Compliance regimes (TCPA, GDPR) often require different consent records per type.

Tools mentioned in this guide

Phone Validator

Pay per result

Google Maps Scraper

Pay per result

Email Verifier

Pay per result

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