Online International Postal Code Validator

About this validator

This version performs a format check for United States ZIP Codes, including 5-digit and ZIP+4 patterns.

It helps prevent simple typing mistakes in flows that depend on international addresses.

Best practices

• Use local validation to reduce errors before form submission.
• Pair it with autocomplete or address verification when you need higher accuracy.
• If you operate in multiple countries, implement country-specific postal code rules.

Important notice

This tool validates only ZIP Code format. It does not confirm address existence or postal deliverability.