**European Economic Area (EEA) developers** > [!NOTE] > If your billing address is in the European Economic Area, effective on 8 July 2025, the [Google Maps Platform EEA Terms of Service](https://cloud.google.com/terms/maps-platform/eea) will apply to your use of the Services. Functionality varies by region. [Learn more](https://developers.google.com/maps/comms/eea/faq.md.txt). The traffic preferences you select balance the accuracy of the route details with request performance in one of two ways: - **Traffic aware** -- Return the most accurate results possible (higher latency). - **Traffic unaware** -- Return the results as quickly as possible (lowest latency). When you make a request, weigh whether it is better to return the most accurate results possible, or to return results as quickly as possible. The Routes API provides options that let you control the quality of the response data versus the latency of the response. ## How to set the traffic level The Routes API provides [RoutingPreference](https://developers.google.com/maps/documentation/routes/reference/rest/v2/RoutingPreference.md.txt) (REST) and [RoutingPreference](https://developers.google.com/maps/documentation/routes/reference/rpc/google.maps.routing.v2.md.txt#routingpreference) (gRPC) that let you specify routing preferences for calculating routes. The default is traffic unaware results. You select traffic options with the `TRAFFIC_UNAWARE`, `TRAFFIC_AWARE` and `TRAFFIC_AWARE_OPTIMAL` routing preferences. Each routing preference produces results that differ in route quality, estimated ETA, and response latency. > [!CAUTION] > **Caution:** Requests using `TRAFFIC_AWARE` and `TRAFFIC_AWARE_OPTIMAL` are billed at a higher rate. [Learn more about billing](https://developers.google.com/maps/documentation/routes/usage-and-billing.md.txt). ### Traffic conditions Traffic conditions characterize the rate of traffic flow: - **Normal traffic**: No congestion with traffic flowing at a normal speed. - **Light to moderate traffic**: Increasing congestion, with traffic flowing at a reduced speed. - **Heavy traffic**: Severe congestion, with heavily reduced traffic speed. ### Traffic unaware `TRAFFIC_UNAWARE` is the default setting. Use this routing preference when you want responses returned the quickest, and approximate routing details are good enough. `TRAFFIC_UNAWARE` routes are calculated without accounting for current traffic conditions. This routing preference results in the fastest request response (lowest latency). If you choose `TRAFFIC_UNAWARE`, the route and duration chosen are based on road network and average time-independent traffic conditions, not current road conditions. Consequently, routes may include roads that are temporarily closed. Results for a given request may vary over time due to changes in the road network, updated average traffic conditions, and the distributed nature of the service. Results may also vary between nearly-equivalent routes at any time or frequency. Here are the responses you'll see: - `duration` - Contains the ETA for the route. - `staticDuration`: The ETA for the route considering only historical traffic information. For `TRAFFIC_UNAWARE`, this contains the same value as `duration`. ### Traffic aware Use this routing preference when you want more accurate routing details than `TRAFFIC_UNAWARE`, and yet you don't mind if responses are returned with a moderate increase in latency. When you set the `TRAFFIC_AWARE` routing preference, the service calculates the route considering current traffic conditions. As a result, the route and route details more accurately reflect real-world conditions. Because this increase in data quality comes at the expense of response latency, performance optimizations are applied to reduce much of the latency. Here are the responses you'll see: - `duration`: The ETA considering real-time traffic information. - `staticDuration` The ETA for the route considering only historical traffic information. ### Traffic aware optimal Use this routing preference when you want results of the highest quality without regard to how long responses take. This routing preference has the longest delay in returning responses (highest latency). When you set the `TRAFFIC_AWARE_OPTIMAL` routing preference, the service calculates the route considering current traffic conditions, but doesn't apply performance optimizations. In this mode, the server performs a more exhaustive search of the road network to find the optimal route. The `TRAFFIC_AWARE_OPTIMAL` routing preference is equivalent to the mode used by [maps.google.com](https://www.google.com/maps) and by the Google Maps mobile app. When you use this option with Compute Route Matrix, the number of elements in a request (number of origins × number of destinations) is limited. For more on Compute Route Matrix limits, see [Compute a route matrix](https://developers.google.com/maps/documentation/routes/compute_route_matrix.md.txt). Here are the responses you'll see: - `duration`: The ETA for the route considering real-time traffic information. - `staticDuration`: The ETA for the route considering only historical traffic information. ## Set departure time (optional) Use this property only for traffic aware requests where the departure time needs to be in the future. If you don't set the `departureTime` property, it defaults to the time that you make the request. Use the `departureTime` property along with the `TRAFFIC_AWARE` and `TRAFFIC_AWARE_OPTIMAL` options when you want to adjust the way the service predicts traffic when choosing a route. - `TRAFFIC_UNAWARE`: **Not recommended** because the choice of route and duration are based on the road network and average time-independent traffic conditions. - `TRAFFIC_AWARE` and `TRAFFIC_AWARE_OPTIMAL`: **Recommended for departures happening in the near future** because these preferences take live traffic conditions into consideration. Live traffic becomes more important and relevant the closer the `departureTime` is to now. The farther ahead you set the departure time into the future, the more consideration is given to historical traffic conditions in selecting routes. ## Example: How to select traffic aware routing The following JSON code demonstrates how to set the `TRAFFIC_AWARE_OPTIMAL` routing preference in a request message entity body. ``` { "origin":{ "location":{ "latLng":{ "latitude":37.419734, "longitude":-122.0827784 } } }, "destination":{ "location":{ "latLng":{ "latitude":37.417670, "longitude":-122.079595 } } }, "travelMode":"DRIVE", "routingPreference":"TRAFFIC_AWARE_OPTIMAL" } ``` ## Configure traffic on polylines The Routes API lets you request information about traffic conditions along a *traffic-aware polyline* . See [Request polylines](https://developers.google.com/maps/documentation/routes/traffic_on_polylines.md.txt) for more information.