---
title: Isochrones | Plaza Docs
description: Compute reachable areas from a point within a given travel time. Returns polygons for car, foot, or bicycle.
---

An isochrone answers “where can I get to from here in N minutes?” — give Plaza a point, a travel time, and a mode, and get back a polygon of the reachable area.

Isochrones are a [premium endpoint](/guides/authentication#premium-endpoints/index.md) — each request counts as 4x.

## Single contour

Terminal window

```
curl -X POST https://plaza.fyi/api/v1/isochrone \
  -H "x-api-key: pk_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "center": { "type": "Point", "coordinates": [2.3522, 48.8566] },
    "time": 600,
    "mode": "foot"
  }'
```

```
import Plaza from "@plazafyi/sdk";


const client = new Plaza();


const iso = await client.v1.isochrone({
  center: { type: "Point", coordinates: [2.3522, 48.8566] },
  contours_minutes: "10",
  mode: "foot",
});
// iso.geometry is a Polygon you can drop straight onto a map
```

```
import plaza


client = plaza.Client()


iso = client.v1.isochrone(
    center={"type": "Point", "coordinates": [2.3522, 48.8566]},
    contours_minutes="10",
    mode="foot",
)
```

```
import "github.com/plazafyi/plaza-go"


client := plaza.NewClient()


iso, _ := client.V1.Isochrone(ctx, plaza.IsochroneParams{
    Center:          plaza.GeoJSONPoint{Type: "Point", Coordinates: []float64{2.3522, 48.8566}},
    ContoursMinutes: "10",
    Mode:            "foot",
})
```

`time` is in seconds. Response — a GeoJSON Feature with a Polygon geometry:

```
{
  "type": "Feature",
  "geometry": {
    "type": "Polygon",
    "coordinates": [[[2.341, 48.850], [2.363, 48.850], [2.363, 48.863], [2.341, 48.863], [2.341, 48.850]]]
  },
  "properties": {
    "time_seconds": 600,
    "mode": "foot",
    "vertices_reached": 342,
    "max_cost_s": 598.4
  }
}
```

## Multiple contours

Pass comma-separated times to get concentric rings in a single request:

Terminal window

```
curl -X POST https://plaza.fyi/api/v1/isochrone \
  -H "x-api-key: pk_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "center": { "type": "Point", "coordinates": [2.3522, 48.8566] },
    "time": "300,600,900",
    "mode": "auto"
  }'
```

```
const iso = await client.v1.isochrone({
  center: { type: "Point", coordinates: [2.3522, 48.8566] },
  contours_minutes: "5,10,15",
  mode: "auto",
});


// 3 features: 5-minute, 10-minute, 15-minute polygons
for (const ring of iso.features) {
  console.log(`${ring.properties.time_seconds}s contour`);
}
```

Returns a FeatureCollection with one Polygon per time value, smallest to largest — ready for layered map display.

## Modes

| Mode      | Network                                          |
| --------- | ------------------------------------------------ |
| `auto`    | Roads, respecting one-ways and turn restrictions |
| `foot`    | Sidewalks, footpaths, trails, pedestrian zones   |
| `bicycle` | Bike lanes, cycleways, shared roads              |

## Use cases

**Site selection.** Generate isochrones from candidate locations and count amenities within each to compare.

**Service area analysis.** Map a fire station’s 5-minute drive radius, or a delivery kitchen’s 20-minute bicycle range.

**Equity mapping.** Generate 15-minute walking isochrones from each hospital to find underserved areas.