USPS ZIP Code Validator & City/State Lookup
Check if a ZIP code is valid and see its primary city and state, using official USPS APIs.
ZIP code must be exactly 5 digits.
About this tool:
- USPS requires ZIP codes to be exactly 5 digits for this lookup.
- Some very new or small ZIPs may not return data yet.
- This checks basic validity and city/state, not full delivery-point addresses.
- For complete address validation with ZIP+4, use our Address Validator tool.
Frequently Asked Questions
What does this ZIP code tool do?
This tool validates whether a 5-digit ZIP code exists in the USPS database and returns the primary city and state associated with that ZIP code.
Does this show ZIP+4?
No, this tool only validates the base 5-digit ZIP code. For ZIP+4 lookup, you need a full street address. Use our Address Validator tool to get the complete ZIP+4 code.
Why is my ZIP not found?
Some reasons a ZIP may not be found: it may be a very new ZIP code not yet in the USPS database, it may have been decommissioned, or there may be a typo. Double-check your ZIP and try again.
Is this official USPS data?
Yes, this tool queries the official USPS Web Tools API to validate ZIP codes and retrieve city/state information directly from USPS databases.
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