Phone Number Formatter Variable for Google Tag Manager

A Google Tag Manager variable template that formats phone numbers to the E.164 standard format. The formatter handles:

• International phone number formatting with country code support
• Removal of special characters (spaces, dashes, parentheses)
• Automatic country code prefixing based on ISO 3166 country codes
• Support for 200+ country codes
• Special handling for Lithuanian numbers (8/0 prefix conversion)

Features

• Converts phone numbers to E.164 format (+[country code][number])
• Preserves existing valid E.164 formatted numbers
• Handles numbers with or without country code prefix
• Supports both + and 00 international prefixes
• Cleans phone numbers of common formatting characters

Usage

• Input a phone number (required)
• Specify country code using ISO 3166 format (optional)
• Returns formatted E.164 phone number with proper country code prefix

Open Source

Initial development was done by Lars Friis.

Maintenance and unit tests added by Giovani Ortolani Barbosa.

Phone Number Formatter Variable for GTM is developed and maintained by Stape Team under the Apache 2.0 license.