simpleParallax.js

simpleParallax.js is a lightweight, easy-to-use React and vanilla-JavaScript library that adds a parallax effect to any image. It works out of the box with React, Next.js, and plain JavaScript — the effect is applied directly to your <img> tags, with no background images needed.

While other plugins can be complex, simpleParallax.js is notable for its simplicity and impressive visual effects. Any image can be used. More info in the case study here.

Give it a try!

Installation

Install the package with your favourite package manager:

npm install simple-parallax-js
yarn add simple-parallax-js
pnpm add simple-parallax-js
bun add simple-parallax-js

For the React version, react and react-dom are peer dependencies (>= 17) — they use the React already installed in your project.

The package is written in TypeScript and ships type definitions for both entry points (React and vanilla), so no extra @types package is needed.

Import it:

//React version
import SimpleParallax from 'simple-parallax-js';

//Vanilla Version
import SimpleParallax from "simple-parallax-js/vanilla";

Initialization

React

Simply add the following JavaScript code:

import SimpleParallax from "simple-parallax-js";

const Component = () => (
  <SimpleParallax>
    <img src={"thumbnail.jpg"} alt={"image"} />
  </SimpleParallax>
)

Vanilla

Giving the following HTML :

 <img class="thumbnail" src="image.jpg" alt="image">

simply add the following JavaScript code :

const image = document.getElementsByClassName('thumbnail');
new SimpleParallax(image);

You can also choose to apply the parallax on multiple images :

const images = document.querySelectorAll('img');
new SimpleParallax(images);

Once simpleparallax has been correctly initialized, it adds the simple-parallax-initialized class on the container.

simpleParallax now works with video :

<video>
  <source src="video.mp4" type="video/mp4">
</video>

var video = document.getElementsByTagName('video');
new SimpleParallax(video);

Settings

Setting	Type	Default	Hint
orientation	String	up	up - right - down - left - up left - up right - down left - down right
scale	Number	1.5	need to be above 1
overflow	Boolean	false
delay	Number	0.4	the delay is in second Watch out, sometimes this delay is causing issue on iOS devices #47
transition	String	'cubic-bezier(0,0,0,1)'	any CSS transition
maxTransition	Number	0	it should be a percentage between 1 and 99
customContainer	String or Node	''	(Vanilla version only)
customWrapper	String	''	the selector of the custom wrapper (Vanilla version only)

You can apply these settings with the following JS code :

React

import SimpleParallax from "simple-parallax-js";

const Component = () => (
  <SimpleParallax 
    delay={0}
    orientation={"down"}
    scale={1.5}
    overflow
    maxTransition={60}
  >
    <img src={"thumbnail.jpg"} alt={"image"} />
  </SimpleParallax>
)

Next

import SimpleParallax from "simple-parallax-js";
import Image from "next/image";

const Component = () => (
  <SimpleParallax 
    delay={0}
    orientation={"down"}
    scale={1.5}
    overflow
    maxTransition={60}
  >
    <Image src={"thumbnail.jpg"} alt={"image"} width={1920} height={1024} />
  </SimpleParallax>
)

Vanilla

var images = document.querySelectorAll('.thumbnail');
new SimpleParallax(images, {
    delay: 0,
    orientation: 'down',
    scale: 1.5,
    overflow: true,
    customContainer: '.container',
    customWrapper: '.wrapper'
});

orientation - String - see example

The parallax effect's orientation, or direction, can be customized. If you choose up, the image will move from bottom to top as you scroll down, and from top to bottom as you scroll up. This same logic applies for all other orientations, including right, down, left, up left, up right, down left, and down right. If two directions are combined, such as down right, the image will move diagonally.

scale - Number - see example

The higher the scale setting, the more pronounced the parallax effect becomes. However, this can cause the image quality to diminish. To mitigate this, if the scale is set at 1.5 and your image width is 500px, simply multiply 500 by 1.5 to get 750. You can then use a 750px image in place of your 500px one to maintain image quality. More information can be found in the case study linked here.

overflow - Boolean - see example

By default, the image scales to create a parallax effect without any overflow on the layout - for a better understanding, review the case study. When overflow is set to true, the image will translate beyond its natural flow, potentially overlapping your content.

delay - Number - see example

Setting a delay prolongs the image's translation even after the user has stopped scrolling, creating a pleasing effect. This delay is measured in seconds. Watch out, sometimes this delay is causing issue on iOS devices #47

transition - String - see example

The transition setting is linked with the delay setting. It applies any CSS transition to the delay setting, such as ease or ease-in-out.

maxTransition - Number - see example

The maxTransition setting controls the extent of the parallax animation. By default, it translates from 0% to 100% of the user's viewport. You can adjust this to any percentage.

customContainer - String or Node - Vanilla version only

Parallax calculations default to the body scroll percentage. However, images may be in a container with its own scroll area. For accurate calculations, set a custom container.

customWrapper - String - Vanilla version only

In some instances, you might want to use your own wrapper instead of the plugin's. Specifying a custom wrapper will add the simpleParallax class and an overflow: hidden style.

Methods

refresh

Refresh a simpleParallax instance (to recalculate all the positions) :

var images = document.querySelectorAll('img');
var instance = new SimpleParallax(images);
instance.refresh();

By default, the refresh method is fired at every window resize.

destroy

Destroy a simpleParallax instance:

var images = document.querySelectorAll('img');
var instance = new SimpleParallax(images);
instance.destroy();

Examples

You can find all the examples here.

Compatibility

Since v7, the library ships modern ES2020 code, so it targets recent evergreen browsers:

Edge	Firefox	Chrome	Safari	Opera	iOS Safari
80+	75+	80+	14+	67+	14+

On older browsers that can't parse ES2020 syntax, the script won't run (you'll need to transpile it yourself, e.g. via your bundler's target). The library also relies on the IntersectionObserver and closest() APIs, which are available in all the browsers above.

Author

Geoffrey Signorato

Contributing

Open an issue or a pull request to suggest changes or additions.