What validations are performed?

Format syntax, country code detection, mobile vs landline classification, and E.164 normalization.

Which countries are supported?

195+ countries using the libphonenumber library.

No. Everything runs locally in your browser.

Process files up to the browser memory limit.

Yes — filter to show only valid or only invalid numbers.

Validate and normalize phone numbers in a CSV column. International format support. Processed entirely in your browser for 10

Your files never leave your device. Processed locally. 100% private.

Unlocking Tool Engine...

Complete your task perfectly in just three straightforward steps.

Drop your CSV file with a phone number column.

Choose which column holds phone numbers.

Download the CSV with a validation status and normalized format column added.

Everything you need to know about the Phone Validator.

Continue working with our suite of free data utilities.

Validate CSV structure, headers, data types, and required fields against a schema. Processed entirely in your browser for 100

Validate a CSV file against a JSON or YAML schema definition. Fast, private, and secure browser-based tool with no signups or

Generate contracts from CSV data using a template. Mail-merge style document creation. Securely process files in your browser