darkroomengineering / lenis

Introduction

Lenis ("smooth" in latin) is a lightweight, robust, and performant smooth scroll library. It's designed by @darkroom.engineering to be simple to use and easy to integrate into your projects. It's built with performance in mind and is optimized for modern browsers. It's perfect for creating smooth scrolling experiences on your website such as WebGL scroll syncing, parallax effects, and much more, see Demo and Showcase.

Read our Manifesto to learn more about the inspiration behind Lenis.

• Sponsors
• Packages
• Showcase
• Installation
• Setup
• Settings
• Properties
• Methods
• Events
• Considerations
• Limitations
• Troubleshooting
• Tutorials
• Plugins
• License

Sponsors

If you’ve used Lenis and it made your site feel just a little more alive, consider sponsoring.

Your support helps us smooth out the internet one library at a time—and lets us keep building tools that care about the details most folks overlook.

Packages

• lenis
• lenis/react
• lenis/vue
• lenis/framer
• lenis/snap

Installation

Using a package manager:

npm i lenis
# or
yarn add lenis
# or
pnpm add lenis

import Lenis from 'lenis'

Using scripts:

<script src="https://unpkg.com/lenis@1.3.18/dist/lenis.min.js"></script> 

Setup

Basic:

// Initialize Lenis
const lenis = new Lenis({
  autoRaf: true,
});

// Listen for the scroll event and log the event data
lenis.on('scroll', (e) => {
  console.log(e);
});

Custom raf loop:

// Initialize Lenis
const lenis = new Lenis();

// Use requestAnimationFrame to continuously update the scroll
function raf(time) {
  lenis.raf(time);
  requestAnimationFrame(raf);
}

requestAnimationFrame(raf);

Recommended CSS:

Import stylesheet:

import 'lenis/dist/lenis.css'

Or link the CSS file:

<link rel="stylesheet" href="https://unpkg.com/lenis@1.3.18/dist/lenis.css">

Or add it manually:

See lenis.css stylesheet

GSAP ScrollTrigger:

// Initialize a new Lenis instance for smooth scrolling
const lenis = new Lenis();

// Synchronize Lenis scrolling with GSAP's ScrollTrigger plugin
lenis.on('scroll', ScrollTrigger.update);

// Add Lenis's requestAnimationFrame (raf) method to GSAP's ticker
// This ensures Lenis's smooth scroll animation updates on each GSAP tick
gsap.ticker.add((time) => {
  lenis.raf(time * 1000); // Convert time from seconds to milliseconds
});

// Disable lag smoothing in GSAP to prevent any delay in scroll animations
gsap.ticker.lagSmoothing(0);

React:

See documentation for lenis/react.

Settings

Option	Type	Default	Description
wrapper	HTMLElement, Window	window	The element that will be used as the scroll container.
content	HTMLElement	document.documentElement	The element that contains the content that will be scrolled, usually wrapper's direct child.
eventsTarget	HTMLElement, Window	wrapper	The element that will listen to wheel and touch events.
smoothWheel	boolean	true	Smooth the scroll initiated by wheel events.
lerp	number	0.1	Linear interpolation (lerp) intensity (between 0 and 1).
duration	number	1.2	The duration of scroll animation (in seconds). Useless if lerp defined.
easing	function	(t) => Math.min(1, 1.001 - Math.pow(2, -10 * t))	The easing function to use for the scroll animation, our default is custom but you can pick one from Easings.net. Useless if lerp defined.
orientation	string	vertical	The orientation of the scrolling. Can be vertical or horizontal.
gestureOrientation	string	vertical	The orientation of the gestures. Can be vertical, horizontal or both.
syncTouch	boolean	false	Mimic touch device scroll while allowing scroll sync (can be unstable on iOS<16).
syncTouchLerp	number	0.075	Lerp applied during syncTouch inertia.
touchInertiaExponent	number	1.7	Manage the strength of syncTouch inertia.
wheelMultiplier	number	1	The multiplier to use for mouse wheel events.
touchMultiplier	number	1	The multiplier to use for touch events.
infinite	boolean	false	Enable infinite scrolling! syncTouch: true is required on touch devices (See example).
autoResize	boolean	true	Resize instance automatically based on ResizeObserver. If false you must resize manually using .resize().
prevent	function	undefined	Manually prevent scroll to be smoothed based on elements traversed by events. If true is returned, it will prevent the scroll to be smoothed. Example: (node) => node.classList.contains('cookie-modal').
virtualScroll	function	undefined	Manually modify the events before they get consumed. If false is returned, the scroll will not be smoothed. Examples: (e) => { e.deltaY /= 2 } (to slow down vertical scroll) or ({ event }) => !event.shiftKey (to prevent scroll to be smoothed if shift key is pressed).
overscroll	boolean	true	Similar to CSS overscroll-behavior (https://developer.mozilla.org/en-US/docs/Web/CSS/overscroll-behavior).
autoRaf	boolean	false	Whether or not to automatically run requestAnimationFrame loop.
anchors	boolean, ScrollToOptions	false	Scroll to anchor links when clicked. If true is passed, it will enable anchor links with default options. If ScrollToOptions is passed, it will enable anchor links with the given options.
autoToggle	boolean	false	Automatically start or stop the lenis instance based on the wrapper's overflow property, ⚠️ this requires Lenis recommended CSS. Safari > 17.3, Chrome > 116 and Firefox > 128 (https://caniuse.com/?search=transition-behavior).
allowNestedScroll	boolean	false	Automatically allow nested scrollable elements to scroll natively. This is the simplest way to handle nested scroll. ⚠️ Can create performance issues since it checks the DOM tree on every scroll event. If that's a concern, use data-lenis-prevent attributes instead.
naiveDimensions	boolean	false	If true, Lenis will use naive dimensions calculation. ⚠️ Be careful, this has a performance impact.
stopInertiaOnNavigate	boolean	false	If true, Lenis will stop inertia when an internal link is clicked.

Properties

Property	Type	Description
animatedScroll	number	Current scroll value
dimensions	object	Dimensions instance
direction	number	1: scrolling up, -1: scrolling down
options	object	Instance options
targetScroll	number	Target scroll value
time	number	Time elapsed since instance creation
actualScroll	number	Current scroll value registered by the browser
lastVelocity	number	last scroll velocity
velocity	number	Current scroll velocity
isHorizontal (getter)	boolean	Whether or not the instance is horizontal
isScrolling (getter)	boolean, string	Whether or not the scroll is being animated, smooth, native or false
isStopped (getter)	boolean	Whether or not the user should be able to scroll
limit (getter)	number	Maximum scroll value
progress (getter)	number	Scroll progress from 0 to 1
rootElement (getter)	HTMLElement	Element on which Lenis is instanced
scroll (getter)	number	Current scroll value (handles infinite scroll if activated)
className (getter)	string	rootElement className

Methods

Method	Description	Arguments
raf(time)	Must be called every frame for internal usage.	time: in ms
scrollTo(target, options)	Scroll to target.	target: goal to reach number: value to scroll in pixels string: CSS selector or keyword (top, left, start, bottom, right, end) HTMLElement: DOM element options offset(number): equivalent to scroll-padding-top lerp(number): animation lerp intensity duration(number): animation duration (in seconds) easing(function): animation easing immediate(boolean): ignore duration, easing and lerp lock(boolean): whether or not to prevent the user from scrolling until the target is reached force(boolean): reach target even if instance is stopped onComplete(function): called when the target is reached userData(object): this object will be forwarded through scroll events
on(id, function)	id can be any of the following instance events to listen.
stop()	Pauses the scroll
start()	Resumes the scroll
resize()	Compute internal sizes, it has to be used if autoResize option is false.
destroy()	Destroys the instance and removes all events.

Events

Event	Callback Arguments
scroll	Lenis instance
virtual-scroll	{deltaX, deltaY, event}

Considerations

Nested scroll

The simplest and most reliable way to handle nested scrollable elements is to use the allowNestedScroll option:

const lenis = new Lenis({
  allowNestedScroll: true,
})

This automatically detects nested scrollable elements and lets them scroll natively. However, this can create performance issues since Lenis needs to check the DOM tree on every scroll event. If you experience performance problems, use data-lenis-prevent instead.

Using HTML attributes

<div data-lenis-prevent>scrollable content</div>

See example

Attribute	Description
data-lenis-prevent	Prevent all smooth scroll events
data-lenis-prevent-wheel	Prevent wheel events only
data-lenis-prevent-touch	Prevent touch events only
data-lenis-prevent-vertical	Prevent vertical scroll events only
data-lenis-prevent-horizontal	Prevent horizontal scroll events only

Using Javascript

<div id="modal">scrollable content</div>

const lenis = new Lenis({
  prevent: (node) => node.id === 'modal',
})

See example

Anchor links

By default, Lenis will prevent anchor links from working while scrolling. To enable them, you must set anchors: true.

new Lenis({
  anchors: true
})

You can also use scrollTo options:

new Lenis({
  anchors: {
    offset: 100,
    onComplete: ()=>{
      console.log('scrolled to anchor')
    }
  }
})

Limitations

• no support for CSS scroll-snap, you must use (lenis/snap)
• capped to 60fps on Safari (source) and 30fps on low power mode
• smooth scroll will stop working over iframe since they don't forward wheel events
• position fixed seems to lag on MacOS Safari pre-M1 (source)
• touch events may behave unexpectedly when syncTouch is enabled on iOS < 16
• nested scroll containers require proper configuration to work correctly

Troubleshooting

• Make sure you use the latest version of Lenis
• Include the recommended CSS
• If using GSAP ScrollTrigger, ensure proper integration (see GSAP ScrollTrigger setup section)
• Test without Lenis to ensure your element/page is scrollable
• Be sure to use autoRaf: true or manually call lenis.raf(time) in your animation loop

Tutorials

• Scroll Animation Ideas for Image Grids by Codrops
• How to Animate SVG Shapes on Scroll by Codrops
• The BEST smooth scrolling library for your Webflow website! (Lenis) by Diego Toda de Oliveira
• Easy smooth scroll in @Webflow with Lenis + GSAP ScrollTrigger tutorial by También Studio

Plugins

• r3f-scroll-rig by 14islands
• locomotive-scroll by Locomotive

License

MIT © darkroom.engineering