US Address Autocomplete API

Autocomplete US addresses as users type

One REST call returns standardized US address suggestions from a few characters, so your forms capture a clean address the first time. Built for developers.

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Try it · live
Start typing a US address

Suggestions appear as you type — standardized, one line each. Click one to fill it in.

— ms 0 used today 500 left today
One request, a ranked list

What comes back

A list of standardized, one-line US addresses, ready to display in a dropdown or store directly.

Suggestions for “1600 pennsylvania”
"1600 Pennsylvania Ave APT 1, Miami Beach, FL 33139-7761"
"1600 Pennsylvania Ave APT 10, Miami Beach, FL 33139-7761"
"1600 Pennsylvania Ave APT 11, Miami Beach, FL 33139-7762"
"1600 Pennsylvania Ave APT 1, Stoughton, MA 02072-2351"
Built for forms

What you get

Clean, complete addresses captured as the user types, not after.

Standardized output

every suggestion is a clean, one-line postal-format address.

Completes from a few characters

start with three characters and the list narrows as they type.

Apartment and suite level

includes APT and STE where the address has them.

From verified address data

suggestions come from real US postal address data, not guesses.
Where teams use it

Common use cases

Checkout & signup formsFewer keystrokes and fewer typos on the address field.
Cut failed deliveriesCapture a valid, complete address the first time.
Speed up any address fieldDrop-in autocomplete for the forms you already have.
Standardize on captureStore clean, consistent addresses from the start.
Copy, paste, ship

A single GET request

Send what the user has typed, get back a ranked list of addresses. No SDK required.

Request
# partial text in, suggestions out
curl "https://api.sthan.io/AutoComplete/USA/Address/1600%20pennsylvania" \
  -H "Authorization: Bearer YOUR_API_KEY"
Response
[
  "1600 Pennsylvania Ave APT 1, Miami Beach, FL 33139-7761",
  "1600 Pennsylvania Ave APT 1, Stoughton, MA 02072-2351",
  "1600 Pennsylvania Ave APT 10, Miami Beach, FL 33139-7761",
  "1600 Pennsylvania Ave APT 10, Stoughton, MA 02072-2351",
  "1600 Pennsylvania Ave APT 11, Miami Beach, FL 33139-7762"
]
Simple pricing

Start free, scale when you need to

A large free tier, then plans by request volume. Annual saves up to about 40%.

Start here
Free
$0
100,000 requests / month
No credit card
Basic
$7 /mo
100,000 requests
higher throughput
Starter
$48 /mo
1,000,000 requests
Business
$180 /mo
5,000,000 requests

Higher volumes and annual discounts on the plans page.

See all plans
Good to know

Questions developers ask

What does the autocomplete API return?

A ranked list of standardized, one-line US addresses that match what the user has typed so far, ready to display in a dropdown or store directly.

How many characters before it suggests?

Start with about three characters. Suggestions refine as the user keeps typing, so the list narrows toward the exact address.

Does it include apartment and suite numbers?

Yes. Where an address has unit detail, the suggestions include the APT or STE, so the captured address is complete.

What do I need to get started?

An email address. Sign up, grab your API key, and send your first request. The free tier gives you 100,000 requests a month with no card on file.

Add autocomplete in two minutes

Sign up, copy your key, make the call. 100,000 requests a month, free.

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