---
title: "Reachable-area polygons."
method: POST
path: "/isochrone/v1"
tags: ["Routing"]
---

# Reachable-area polygons.

`POST /isochrone/v1`

## Request

- Base URL: `https://api.rijwind.com`
- URL: `https://api.rijwind.com/isochrone/v1`
- Auth: HTTP bearer

Compute reachable-area polygons (isochrones) from one or more origins. Each contour is a time or distance band, returned as a GeoJSON Feature.

**Quota cost:** `5 × L × C` units per call (`L = locations`, `C = contours`). Capped at `L × C ≤ 4`; requests beyond that return 400.

## Request body

- IsochroneRequest
  - `contours` IsochroneContour[], required: One contour per reachable-area band. The product `len(locations) × len(contours)` must not exceed 4.
    - `color` string, nullable: Hex color without leading hash.
    - `distance` number, double, nullable
    - `time` number, double, nullable
  - `costing` 'auto' | 'bicycle' | 'pedestrian', required: Routing profile. `auto` (car), `bicycle`, or `pedestrian` (foot).
  - `locations` LngLat[], required
    - `lat` number, double, required
    - `lon` number, double, required
  - `polygons` boolean, nullable: Return polygons instead of GeoJSON LineStrings.

## Response `200`

Isochrone response.

- IsochroneResponse: GeoJSON FeatureCollection with one feature per contour.
  - `features` IsochroneFeature[], required
    - `geometry` unknown, required
    - `properties` IsochroneFeatureProperties, required
      - `color` string, nullable
      - `contour` number, double, nullable
      - `metric` string, nullable
    - `type` string, required
  - `type` string, required

## Other responses

- `400`: Body malformed, costing unsupported, or `L × C > 4`.
- `401`: Missing, malformed, or revoked API key.
- `429`: Monthly quota exhausted.

---

[API](https://skmtc.dev/rijwind/apis/rijwind-api.md) · [All operations](https://skmtc.dev/rijwind/apis/rijwind-api/llms.txt) · [OpenAPI document](https://skmtc.dev/rijwind/apis/rijwind-api/revisions/01d72fb6aa4d?raw)