---
title: "Heatmap layer weight (heatmap helper) | JavaScript maps SDK"
description: "Use data properties as weight values for heatmap layers."
---
> 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 weight (heatmap helper)
This example shows how to add a heatmap layer into a map by utilizing a property as the weight. To accomplish this, the heatmap layer helper is employed. If you wish to access the [earthquake sample data](../../assets/earthquakes.geojson).
Incorporating a property as the weight **MUST** be paired with a ramping description. By configuring these options, earthquakes with magnitudes close to zero will be displayed with reduced intensity, while earthquakes with magnitudes of 6 or higher will be portrayed at their maximum intensity.
### NPM module setup
```bash
npm install --save @maptiler/sdk
```
#### main.js
```js
import { Map, MapStyle, config, 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: 10.82,
center: [-112.5033, 46.8634],
style: MapStyle.DATAVIZ.LIGHT
});
map.on('load', async function () {
await helpers.addHeatmap(map, {
data: 'YOUR_MAPTILER_DATASET_ID_HERE',
property: "mag", // use the earthquake magnitude to add weight to each point
weight: [
{propertyValue: 0, value: 0},
{propertyValue: 6, value: 1},
],
});
});
```
#### index.html
```html
Heatmap layer weight (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 custom radius (heatmap helper)](https://docs.maptiler.com/sdk-js/examples/helper-heatmap-ramped-radius/)
Examples
Implement custom zoom-ramping radius in heatmap layers.
### [Point layer cluster (point helper)](https://docs.maptiler.com/sdk-js/examples/helper-point-cluster/)
Examples
Add clustered point layer using MapTiler point helper.