---
category: Elements
---

# useElementSize

Reactive size of an HTML element. [ResizeObserver MDN](https://developer.mozilla.org/en-US/docs/Web/API/ResizeObserver)

## Usage

```vue
<script setup lang="ts">
import { useElementSize } from '@vueuse/core';
import { useTemplateRef } from 'vue';

const el = useTemplateRef('el');
const { width, height } = useElementSize(el);
</script>

<template>
  <div ref="el">Height: {{ height }} Width: {{ width }}</div>
</template>
```

## Component Usage

```vue
<template>
  <UseElementSize v-slot="{ width, height }">
    Width: {{ width }} Height: {{ height }}
  </UseElementSize>
</template>
```

## Directive Usage

```vue
<script setup lang="ts">
import { vElementSize } from '@vueuse/components';

function onResize({ width, height }: { width: number; height: number }) {
  console.log(width, height);
}
</script>

<template>
  <textarea v-element-size="onResize" />
  <!-- with options -->
  <textarea v-element-size="[onResize, { width: 100, height: 100 }, { box: 'content-box' }]" />
</template>
```

## Type Declarations

```ts
export interface ElementSize {
  width: number;
  height: number;
}
/**
 * Reactive size of an HTML element.
 *
 * @see https://vueuse.org/useElementSize
 */
export declare function useElementSize(
  target: MaybeComputedElementRef,
  initialSize?: ElementSize,
  options?: UseResizeObserverOptions,
): {
  width: ShallowRef<number, number>;
  height: ShallowRef<number, number>;
  stop: () => void;
};
export type UseElementSizeReturn = ReturnType<typeof useElementSize>;
```
