Isochrone API

The Isochrone API calculates the area you can reach from a point within a given travel time. The result is a polygon you can display on a map.

This is useful for showing delivery zones, service areas, or commute ranges.

Base URL

https://routing.maptoolkit.net/isochrone

Authentication

Add your API key as ?api_key=YOUR_API_KEY to every request. See Authentication for details.

Parameters

Parameter	Type	Required	Description
`point`	`lat,lng`	Yes	The starting point.
`time`	number	Yes	Travel time in minutes.
`routeType`	string	Yes	Vehicle type: `car`, `bike`, `foot`, or `transit`. Transit is available only in NRW, Germany.
`format`	string	No	Set to `geojson` to get a GeoJSON geometry object. Required for transit isochrones.
`departure`	date string	No	Departure time for transit routing.

Response

An array of [lat, lng] coordinate pairs that form a polygon.

GET https://routing.maptoolkit.net/isochrone?point=47.268,11.400&time=10&routeType=bike&api_key=YOUR_API_KEY

This is a response to the HTTP GET request shown above:

[
  [
    47.27599805,
    11.39406835
  ],
  [
    47.27524085,
    11.3925068
  ],
  [
    47.2742211,
    11.3920193
  ],
  [
    47.2732573,
    11.3914051
  ],
  ...
]

GeoJSON Response

If you set the URL parameter format=geojson the response is a GeoJSON Feature, not a bare geometry:

{
  "type": "Feature",
  "geometry": {
    "type": "Polygon",
    "coordinates": [[[11.38381165, 47.26794595], [11.38252845, 47.26719565], ...]]
  },
  "properties": {
    "bucket": 0
  }
}

Two things follow from that. A MapLibre geojson source accepts the response as-is, because a Feature is valid GeoJSON on its own. Anything that expects a geometry has to read response.geometry rather than the response itself.

Field	Description
`type`	Always `Feature`.
`geometry`	A `Polygon` whose coordinates are `[lng, lat]`.
`properties.bucket`	Index of the band this polygon belongs to, counting from `0`. A single-time request always returns `0`.

Note: The coordinate order differs between the two response shapes. The GeoJSON geometry uses [lng, lat], the standard array response uses [lat, lng].

Examples

Working examples for this API, each with copyable source:

Maptoolkit Maps JS

Show a draggable isochrone area on a Maptoolkit map using the built-in IsochroneControl.

MapLibre GL JS

Fetch a walking isochrone and draw it as a filled polygon on a MapLibre GL map.

Leaflet

Fetch a walking isochrone and draw it as a polygon on a Leaflet map.

Locations Inside an Isochrone

Test your own points against an isochrone polygon to find which of them are reachable in time.

Travel Time Bands

Stack several isochrones as shaded bands to show 5, 10 and 15 minutes on foot from one point.

Errors

Errors return the HTTP status code with a plain-text message in the body.

Status	Meaning
`403`	The API key is missing (`Access denied!`) or not recognized (`Api-key not found!`). See First Steps.
`400`	A parameter failed validation, or the routing engine rejected the request.

Common `400` messages

Message	Cause
`Missing required parameter: point`	`point` is missing or empty.
`Parameter 'time' must be a positive number`	`time` is not a positive number.
`Parameter 'time' must not exceed 60 minutes`	`time` is above the 60 minute maximum.
`Cannot parse departure time!`	`departure` is not a valid date string.
`format=geojson is mandatory on isochrone request for transit!`	`routeType=transit` requires `format=geojson`.

Errors from the upstream routing engine are forwarded as-is.

Rate limits

Limits are monthly request quotas tied to your plan rather than a per-second rate: the service returns no RateLimit-* or Retry-After headers. Current allowances are on the pricing page.

The free Basic plan has a hard limit, so requests are refused once it is reached. On Pro and Ultra, requests past the allowance are billed rather than refused. Enterprise plans use a flexible limit.

Calls to this API count toward your plan’s API request allowance, which is the smaller of the two allowances.

Pricing

Self-service plans (Basic, Pro, and Ultra) are billed through RapidAPI; see RapidAPI for how to subscribe and authenticate. Plan limits and prices are listed on the Maptoolkit pricing page. Enterprise customers call the native hosts directly with a Maptoolkit API key.