Isochrone API

Introduction

An isochrone represents a path that joins all the points with the same travel time or travel distance from a specific point of reference. NextBillion.ai’s Isochrone API calculates the regions that can be reached within a designated time frame from a given location. It returns these accessible areas as contours of polygons or lines, which can be conveniently displayed on a map. Additionally, this API also enables the creation of contours based on distance. With the Isochrone API users can easily define serviceable areas or delivery zones based on travel times from a starting location

The Isochrone API can be accessed through the HTTPS GET method. Let’s take a look at the features and properties of this service.

Request Parameters

Response Schema

Sample Queries

GET Request Example 1

Let’s build a basic Isochrone API request to determine the area that a car can cover within a driving time of 5 minutes when a given coordinates is the starting point.

Request

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curl --location 'https://api.nextbillion.io/isochrone/json?key=<your_api_key>&coordinates=34.04715844,-118.24977187&mode=car&contours_minutes=5'

Response

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{
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    "features": "[...]",
3
    "type": "FeatureCollection"
4
}

Here is how the above response looks on a map. We can easily visualize the area reachable within 5 minutes. It is enclosed by a contour line or a polygon around the starting point provided in the coordinates parameter

GET Request Example 2

Taking the next step for the same coordinates point and same contour_minutes value, let’s expand the request to configure the following parameters:

• set mode = truck to see what areas can a truck cover

• set denoise to a low value to receive exact pockets of areas that can or cannot be covered within the given time

Request

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curl --location 'https://api.nextbillion.io/isochrone/json?key=<your_api_key>&coordinates=34.03849472,-118.24424250&mode=truck&contours_minutes=5&denoise=0.001'

Response

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{
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    "features": "[...]",
3
    "type": "FeatureCollection"
4
}

Here is how the above response looks. Notice a smaller polygon appears within the large one when we set denoise to a low value. This smaller polygon encloses the area that can not be reached by a truck within 20 minutes from the starting point.

API Query Limits

• Only one of contours_meters or contours_minutes should be provided in the input request. A 400 error is returned if none of them are provided. We do not recommend using both contours_meters or contours_minutes together in a request.

• Up to 4 isochrones can be requested using the contours_minutes parameter with a maximum allowed value of 40 minutes.

• Up to 4 isochrones can be requested using the contours_meters parameter with a maximum allowed value of value of 60000 meters.

• NextBillion.ai allows a maximum rate limit of 6000 queries per minute or 100 queries/second for continuous requests. Note: We can increase the quota if needed, on request. Contact [email protected] for more details.

API Error Codes