Using session tokens

Session tokens group the query and selection phases of a user autocomplete search into a discrete session for billing purposes.

Create a session token

Users are responsible for generating unique session tokens for each session. Google recommends using version 4 UUIDs.

Example

As the user types a query, an autocomplete request is called every few keystrokes (not per-character), and a list of possible results is returned. When the user makes a selection from the result list, the selection counts as a request, and all of the requests made during the search are bundled and counted as a single request. If the user selects a place, the search query is available at no charge, and only the Place data request is charged. If the user does not make a selection within a few minutes of the beginning of the session, only the search query is charged.

Let's examine this flow of events from the perspective of an app.

1. A user begins typing a query to search for "Paris, France".
2. Upon detecting user input, the app creates a new session token, "Token A".
3. As the user types, the API makes an autocomplete request every few characters, displaying a new list of potential results for each:
   "P"
   "Par"
   "Paris,"
   "Paris, Fr"
   
4. When the user makes a selection:
• All requests resulting from the query are grouped and added to the session represented by "Token A", as a single request.
• The user's selection is counted as a Place Detail request, and added to the session represented by "Token A".
5. The session is concluded, and the app discards "Token A".

For more information about how Autocomplete requests are billed, see Usage and Billing.