Address verification & ZIP+4 lookup

Type a US address to check it and get its full ZIP+4 (the last 4 digits).

Check a US address and get its ZIP+4. Free, no sign-up.

Addresses are checked through our secure proxy. Bot checks use Cloudflare Turnstile. Each device can run 5 live checks per day; repeats of the same address are free.

How it works

  1. Enter the street, city and state (ZIP is optional).
  2. Complete the quick bot check.
  3. Get the standardized address, the ZIP+4 and whether USPS recognizes the exact unit.

FAQ

Is this free?

Yes. Each device can run 5 live address checks per day. Repeating an address you already checked is free and does not count.

Where does the ZIP+4 come from?

Addresses are matched against USPS ZIP+4 data through the Geocodio geocoding service.

What does “closest match” mean?

The street address was found, but USPS did not recognize the exact apartment or suite number. Double-check the unit.

Why is there no ZIP+4?

Some addresses are not USPS delivery points (for example vacant land or some rural locations), so they have no ZIP+4.

Do you store my address?

Results are cached under a one-way hash for up to 90 days so repeats are instant. We do not link addresses to you.