---
title: "Heatmap layer radius and weight by property (heatmap helper) | JavaScript maps SDK"
description: "Control heatmap radius and weight using data properties."
---
> For AI agents: a documentation index is available at [/llms.txt](https://docs.maptiler.com/llms.txt). Markdown versions of all pages are available by appending .md to any URL.
# Heatmap layer radius and weight by property (heatmap helper)
This example shows how to add a heatmap layer to the map, simultaneously controlling the radius and weight based on a property using the heatmap layer helper. Download the sample data [here](../../assets/schools.geojson).
Since zoomCompensation is disabled in this example, it is recommended to view the map specifically on z12.
### NPM module setup
```bash
npm install --save @maptiler/sdk
```
#### main.js
```js
import { Map, MapStyle, config, ColorRampCollection, helpers } from '@maptiler/sdk';
import '@maptiler/sdk/dist/maptiler-sdk.css';
config.apiKey = 'YOUR_MAPTILER_API_KEY_HERE';
const map = new Map({
container: 'map',
zoom: 12,
center: [-77.01162, 38.94189],
style: MapStyle.DATAVIZ.DARK
});
map.on('load', async function () {
await helpers.addHeatmap(map, {
data: 'schools.geojson',
property: "students",
radius: [
{propertyValue: 100, value: 15},
{propertyValue: 800, value: 50},
],
weight: [
{propertyValue: 100, value: 0.1},
{propertyValue: 800, value: 1},
],
colorRamp: ColorRampCollection.MAGMA,
zoomCompensation: false,
opacity: 0.7,
intensity: 1.2,
});
});
```
#### index.html
```html
Heatmap layer radius and weight by property (heatmap helper) | NPM example
```
#### style.css
```css
body {margin: 0; padding: 0;}
#map {position: absolute; top: 0; bottom: 0; width: 100%;}
```
### Basic JavaScript setup
```html
Heatmap helper
```
## Related examples
### [Heatmap layer (heatmap helper)](https://docs.maptiler.com/sdk-js/examples/helper-heatmap-minimal/)
Examples
Quickly add a heatmap layer using the heatmap helper.
### [Create a heatmap layer](https://docs.maptiler.com/sdk-js/examples/heatmap-layer/)
Examples
Visualize point data frequency using a custom heatmap layer.
### [Heatmap layer no zoom compensation (heatmap helper)](https://docs.maptiler.com/sdk-js/examples/helper-heatmap-no-zoom-compensation/)
Examples
Create heatmap layers without zoom-based radius compensation.
### [Point layer cluster (point helper)](https://docs.maptiler.com/sdk-js/examples/helper-point-cluster/)
Examples
Add clustered point layer using MapTiler point helper.