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Preline UI is an open-source set of prebuilt UI components based on the utility-first Tailwind CSS framework.
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# Textarea Autoheight
Automatically sets the height of the textarea.
[](https://www.npmjs.com/package/@preline/textarea-auto-height) [](https://opensource.org/licenses/MIT) [](https://preline.co/plugins/textarea-autoheight.html)
## Contents
- [Overview](#overview)
- [Installation](#installation)
- [Basic usage](#basic-usage)
- [Configuration Options](#configuration-options)
- [JavaScript API](#javascript-api)
- [Common Patterns](#common-patterns)
- [License](#license)
## Overview
The Textarea Autoheight component automatically adjusts the height of a textarea element based on its content. As users type, the textarea expands or contracts to fit the text, eliminating the need for scrollbars.
**Key Features:**
- Automatic height adjustment based on content
- Smooth resizing as user types
- Configurable default height
- Programmatic control via JavaScript API
- No scrollbars needed
## Installation
To get started, install Textarea Autoheight plugin via npm, else you can skip this step if you are already using Preline UI as a package.
```bash
npm i @preline/textarea-auto-height
```
### CSS
[`@import`](https://tailwindcss.com/docs/functions-and-directives#import-directive) the plugin's CSS file into your Tailwind CSS file.
```css
@import "tailwindcss";
/* @preline/textarea-auto-height */
@import "./node_modules/@preline/textarea-auto-height/theme.css";
```
### JavaScript
Include the JavaScript that powers the interactive elements near the end of your `</body>` tag:
```html
<script src="./node_modules/@preline/textarea-auto-height/index.js"></script>
```
### Manual Initialization
Use the `non-auto` entry if you need manual initialization. In this mode, automatic initialization on page load is not included, so the component should be initialized explicitly.
```html
<script type="module">
import HSTextareaAutoHeight from "@preline/textarea-auto-height/non-auto.mjs";
new HSTextareaAutoHeight(document.querySelector("#textarea"));
</script>
```
### Via Bundler
When using a bundler (Vite, webpack, etc.), import the plugin directly as an ES module.
`@preline/textarea-auto-height` is the auto-init entry: it scans the DOM and initializes matching elements automatically.
```js
import "@preline/textarea-auto-height";
```
`@preline/textarea-auto-height/non-auto` is the manual entry: use it when you want explicit control over when initialization happens, either via `autoInit()` or by creating a specific instance yourself.
```js
import HSTextareaAutoHeight from "@preline/textarea-auto-height/non-auto";
HSTextareaAutoHeight.autoInit();
// Or initialize a specific element manually
const el = document.querySelector("#textarea");
if (el) new HSTextareaAutoHeight(el);
```
### TypeScript
This package ships with TypeScript type definitions. No additional `@types/` package is needed.
## Basic usage
The following example demonstrates the minimal HTML structure required for a textarea autoheight component. This is a base template without custom styling - you can apply your own CSS classes and styles as needed. The textarea automatically adjusts its height as content is entered.
```html
<textarea data-hs-textarea-auto-height></textarea>
```
**Structure Requirements:**
- `data-hs-textarea-auto-height`: Required on the textarea element
- Standard `<textarea>` element
**Initial State:**
- Textarea starts at default height (or configured `defaultHeight`)
- Height adjusts automatically as content is entered or removed
## Configuration Options
### Data Options
Data options are specified in the `data-hs-textarea-auto-height` attribute.
| Attribute | Target Element | Type | Default | Description |
| --- | --- | --- | --- | --- |
| `data-hs-textarea-auto-height` | Textarea element | - | - | If this attribute is added to the textarea, then automatic height calculation according to the content is enabled. Should be added to the textarea itself. |
| `:defaultHeight` | Inside `data-hs-textarea-auto-height` | number | `0` | Sets the default height (when no text is entered). When set to `0`, the textarea uses its natural height. |
**Example:**
```html
<textarea data-hs-textarea-auto-height='{
"defaultHeight": 50
}'></textarea>
```
## JavaScript API
The `HSTextareaAutoHeight` object is available in the global `window` object after the plugin is loaded.
### Instance Methods
These methods are called on a textarea autoheight instance.
| Method | Parameters | Return Type | Description |
| --- | --- | --- | --- |
| `destroy()` | None | `void` | Destroys the textarea autoheight instance, removes all generated markup, classes, and event listeners. Use when removing textarea autoheight from DOM. |
### Static Methods
These methods are called directly on the `HSTextareaAutoHeight` class.
| Method | Parameters | Return Type | Description |
| --- | --- | --- | --- |
| `HSTextareaAutoHeight.getInstance(target, isInstance)` | `target`: `HTMLTextAreaElement \| string` (CSS selector)<br>`isInstance`: `boolean` (optional) | `HSTextareaAutoHeight \| { id: string \| number, element: HSTextareaAutoHeight } \| null` | Returns the textarea autoheight instance associated with the target. If `isInstance` is `true`, returns collection item object `{ id, element }` where `element` is the `HSTextareaAutoHeight` instance. If `isInstance` is `false` or omitted, returns the `HSTextareaAutoHeight` instance directly. Returns `null` if textarea autoheight instance is not found. |
### Usage Examples
**Example 1: Destroying textarea autoheight instance**
```javascript
const instance = HSTextareaAutoHeight.getInstance('#hs-textarea-autoheight', true);
if (instance) {
const { element } = instance;
const destroyBtn = document.querySelector('#hs-destroy-btn');
destroyBtn.addEventListener('click', () => {
element.destroy();
});
}
```
**Example 2: Getting instance and accessing properties**
```javascript
// Get the textarea autoheight instance
const instance = HSTextareaAutoHeight.getInstance('#hs-textarea-autoheight', true);
if (instance) {
const { element } = instance;
// Access instance properties
console.log('Default height:', element.defaultHeight);
// Clean up when removing from DOM
function removeTextareaAutoheight() {
element.destroy();
}
}
```
**Example 3: Destroying textarea autoheight instance**
```javascript
const instance = HSTextareaAutoHeight.getInstance('#hs-textarea-autoheight', true);
if (instance) {
const { element } = instance;
const removeBtn = document.querySelector('#hs-remove-btn');
removeBtn.addEventListener('click', () => {
// Clean up before removing from DOM
element.destroy();
// Now safe to remove the element
document.querySelector('#hs-textarea-autoheight').remove();
});
}
```
## Common Patterns
### Pattern 1: Custom Default Height
Set a custom default height for the textarea.
```html
<textarea data-hs-textarea-auto-height='{
"defaultHeight": 100
}'></textarea>
```
### Pattern 2: Multiple Autoheight Textareas
Apply autoheight to multiple textareas.
```html
<textarea id="hs-comment-first" data-hs-textarea-auto-height></textarea>
<textarea id="hs-comment-second" data-hs-textarea-auto-height></textarea>
```
## License
Copyright (c) 2026 Preline Labs.
Licensed under the [MIT License](https://opensource.org/licenses/MIT).