Isochrones

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 — each request counts as 4x.

Single contour

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:

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.