dotLottie Implementation Guidelines

Name: dotlottie-web
Rating: 76
Author: LottieFiles

You are an expert at implementing Lottie animations using dotLottie runtimes. Follow these guidelines when working with dotLottie in web projects.

Package Selection

Use `@lottiefiles/dotlottie-web` when:

•You need direct canvas control
•Building framework-agnostic code
•Maximum performance is critical
•You want the smallest bundle

Use `@lottiefiles/dotlottie-react` when:

•Building React applications
•You want declarative component API
•You need React lifecycle integration

Installation

bash

# Web (vanilla JS, Vue, Svelte, etc.)
npm install @lottiefiles/dotlottie-web

# React
npm install @lottiefiles/dotlottie-react

Basic Implementation

Vanilla JavaScript

typescript

import { DotLottie } from '@lottiefiles/dotlottie-web';

const dotLottie = new DotLottie({
  canvas: document.getElementById('canvas') as HTMLCanvasElement,
  src: 'https://example.com/animation.lottie',
  autoplay: true,
  loop: true,
});

React

tsx

import { DotLottieReact } from '@lottiefiles/dotlottie-react';

function Animation() {
  return (
    <DotLottieReact
      src="https://example.com/animation.lottie"
      autoplay
      loop
    />
  );
}

React with Instance Control

tsx

import { useRef } from 'react';
import { DotLottieReact } from '@lottiefiles/dotlottie-react';
import type { DotLottie } from '@lottiefiles/dotlottie-web';

function Animation() {
  const dotLottieRef = useRef<DotLottie | null>(null);

  return (
    <DotLottieReact
      src="https://example.com/animation.lottie"
      dotLottieRefCallback={(dotLottie) => (dotLottieRef.current = dotLottie)}
    />
  );
}

.lottie vs .json

Always prefer .lottie format over .json:

•Smaller file size (compressed)
•Supports multiple animations in one file
•Embedded assets (images, fonts)
•State machines for interactivity
•Theming with slots

Web Workers (Recommended for Performance)

Use DotLottieWorker to offload animation rendering to a Web Worker, keeping the main thread free for UI interactions:

Basic Worker Usage

typescript

import { DotLottieWorker } from '@lottiefiles/dotlottie-web';

const dotLottie = new DotLottieWorker({
  canvas: document.getElementById('canvas') as HTMLCanvasElement,
  src: 'https://example.com/animation.lottie',
  autoplay: true,
  loop: true,
});

Worker Grouping (Multiple Animations)

By default, all DotLottieWorker instances share the same worker. Group animations into separate workers using workerId:

typescript

// Hero animation in its own worker
const heroAnimation = new DotLottieWorker({
  canvas: heroCanvas,
  src: 'hero.lottie',
  workerId: 'hero-worker',
});

// UI animations share a different worker
const buttonAnimation = new DotLottieWorker({
  canvas: buttonCanvas,
  src: 'button.lottie',
  workerId: 'ui-worker',
});

When to Use Workers

•
Use DotLottieWorker for:
- •Multiple simultaneous animations
- •Complex animations with many layers
- •Animations running alongside heavy JS operations
- •Mobile devices where main thread performance is critical
•
Use regular DotLottie for:
- •Single simple animations
- •When you need synchronous frame access
- •SSR environments (workers not available)

React with Workers

tsx

import { DotLottieWorkerReact } from '@lottiefiles/dotlottie-react';

function Animation() {
  return (
    <DotLottieWorkerReact
      src="animation.lottie"
      autoplay
      loop
      workerId="my-worker" // Optional: dedicate to specific worker
    />
  );
}

State Machines (Interactivity)

State machines enable interactive animations without code. See the State Machine Guide for details.

typescript

const dotLottie = new DotLottie({
  canvas,
  src: 'interactive.lottie', // Contains state machine
  autoplay: true,
});

// Fire events to trigger state transitions
dotLottie.stateMachineFireEvent('click');
dotLottie.stateMachineFireEvent('hover');
dotLottie.stateMachineFireEvent('custom-event');

// Set numeric/boolean/string inputs for state conditions
// See: https://github.com/LottieFiles/dotlottie-web/wiki/dotLottie-State-Machine-Guide#working-with-inputs
dotLottie.stateMachineSetNumericInput('progress', 0.5);
dotLottie.stateMachineSetBooleanInput('isActive', true);
dotLottie.stateMachineSetStringInput('mode', 'dark');

State Machine Events

•click - User click/tap
•hover - Mouse enter
•unhover - Mouse leave
•complete - Animation finished
•Custom events defined in the state machine

Theming with Slots

Slots allow runtime color/value customization. Themes follow the dotLottie 2.0 spec.

typescript

const dotLottie = new DotLottie({
  canvas,
  src: 'themed.lottie',
  themeId: 'dark-mode', // Use embedded theme by ID
});

// Or apply theme data directly (JSON string per dotLottie 2.0 spec)
// See: https://dotlottie.io/spec/2.0/#themes
dotLottie.setThemeData(JSON.stringify({
  rules: [
    { id: 'primary-color', value: [1, 0.34, 0.13] }, // RGB values 0-1
  ]
}));

Dynamic Slot Overriding

Slots enable runtime customization of animated properties using typed APIs. Available slot types: color, scalar, vector, gradient, text, image.

Key APIs: getSlotIds(), getSlotType(), setColorSlot(), setScalarSlot(), setVectorSlot(), setGradientSlot(), setTextSlot(), resetSlot(), clearSlots().

For complete API reference with code examples for each slot type, animated keyframes, resetting, bulk updates, common use cases (branding, dark mode, progress indicators), and React integration, see Dynamic Slots Reference.

Markers & Segments

Playing Specific Segments

typescript

// Play frames 0-60
dotLottie.setSegment(0, 60);
dotLottie.play();

// Play by marker name (defined in animation)
dotLottie.setMarker('intro');
dotLottie.play();

Getting Markers

typescript

const markers = dotLottie.markers();
// Returns: [{ name: 'intro', time: 0, duration: 60 }, ...]

Event Handling

typescript

dotLottie.addEventListener('load', () => {
  console.log('Animation loaded');
});

dotLottie.addEventListener('play', () => {
  console.log('Playing');
});

dotLottie.addEventListener('complete', () => {
  console.log('Animation completed');
});

dotLottie.addEventListener('frame', ({ currentFrame }) => {
  console.log('Frame:', currentFrame);
});

// Clean up
dotLottie.removeEventListener('load', handler);

Performance Best Practices

1. Use Web Workers for Complex Animations

typescript

import { DotLottieWorker } from '@lottiefiles/dotlottie-web';

// Offload rendering to worker thread
const dotLottie = new DotLottieWorker({
  canvas,
  src: 'complex-animation.lottie',
});

2. Lazy Load Animations

typescript

// Only load when visible
const observer = new IntersectionObserver((entries) => {
  entries.forEach(entry => {
    if (entry.isIntersecting) {
      loadAnimation();
      observer.disconnect();
    }
  });
});
observer.observe(container);

3. Auto-Freeze is Enabled by Default

DotLottie automatically freezes animations when they're not visible (offscreen). To disable this behavior:

typescript

const dotLottie = new DotLottie({
  canvas,
  src: 'animation.lottie',
  renderConfig: {
    freezeOnOffscreen: false, // Disable auto-freeze (not recommended)
  },
});

4. Device Pixel Ratio

By default, devicePixelRatio is set to 75% of the actual value for better performance. For full retina quality (with higher performance cost):

typescript

const dotLottie = new DotLottie({
  canvas,
  src: 'animation.lottie',
  renderConfig: {
    devicePixelRatio: window.devicePixelRatio, // Full retina (higher CPU/GPU)
  },
});

5. Clean Up (Vanilla JS only)

typescript

// Always destroy when done (vanilla JS)
dotLottie.destroy();

Note: DotLottieReact handles cleanup automatically on unmount - no manual cleanup needed.

6. Frame Interpolation Control

typescript

const dotLottie = new DotLottie({
  canvas,
  src: 'animation.lottie',
  useFrameInterpolation: true,  // Smooth playback (default)
  // useFrameInterpolation: false, // Match original AE frame rate
});

Multi-Animation Files

A single .lottie file can contain multiple animations:

typescript

// Load specific animation by ID
dotLottie.loadAnimation('animation-2');

// Get all animation IDs
const animations = dotLottie.manifest?.animations;
// Returns: [{ id: 'animation-1' }, { id: 'animation-2' }]

Canvas Sizing

Set canvas size via CSS styles (recommended). DotLottie will automatically determine the optimal drawing area:

html

<canvas id="canvas" style="width: 400px; height: 400px;"></canvas>

Auto-Resize to Container

Use the autoResize render config to automatically resize when the container changes:

typescript

const dotLottie = new DotLottie({
  canvas,
  src: 'animation.lottie',
  renderConfig: {
    autoResize: true, // Canvas resizes to fit container
  },
});

Common Patterns

Play on Hover

typescript

canvas.addEventListener('mouseenter', () => dotLottie.play());
canvas.addEventListener('mouseleave', () => dotLottie.pause());

Play on Click (Once)

typescript

canvas.addEventListener('click', () => {
  dotLottie.setFrame(0);
  dotLottie.setLoop(false);
  dotLottie.play();
});

Scrub with Scroll

typescript

window.addEventListener('scroll', () => {
  const progress = window.scrollY / (document.body.scrollHeight - window.innerHeight);
  const frame = progress * dotLottie.totalFrames;
  dotLottie.setFrame(frame);
});

Loading States (React)

tsx

function Animation() {
  const [isLoaded, setIsLoaded] = useState(false);

  return (
    <>
      {!isLoaded && <Skeleton />}
      <DotLottieReact
        src="animation.lottie"
        style={{ opacity: isLoaded ? 1 : 0 }}
        dotLottieRefCallback={(dotLottie) => {
          dotLottie.addEventListener('load', () => setIsLoaded(true));
        }}
      />
    </>
  );
}

Responsive Animation

tsx

function ResponsiveAnimation() {
  return (
    <DotLottieReact
      src="animation.lottie"
      autoplay
      loop
      style={{ width: '100%', maxWidth: '400px' }}
      renderConfig={{ autoResize: true }}
    />
  );
}

Debugging

typescript

// Check if loaded
console.log('Loaded:', dotLottie.isLoaded);

// Get animation info
console.log('Duration:', dotLottie.duration);
console.log('Total Frames:', dotLottie.totalFrames);
console.log('Current Frame:', dotLottie.currentFrame);
console.log('Is Playing:', dotLottie.isPlaying);
console.log('Loop:', dotLottie.loop);
console.log('Speed:', dotLottie.speed);

// Get manifest (for .lottie files)
console.log('Manifest:', dotLottie.manifest);

Error Handling

typescript

dotLottie.addEventListener('loadError', (error) => {
  console.error('Failed to load animation:', error);
  // Show fallback UI
});

SSR / Next.js Considerations

dotLottie requires browser APIs. For SSR frameworks:

tsx

import dynamic from 'next/dynamic';

const DotLottieReact = dynamic(
  () => import('@lottiefiles/dotlottie-react').then(mod => mod.DotLottieReact),
  { ssr: false }
);

function Animation() {
  return <DotLottieReact src="animation.lottie" autoplay loop />;
}

Resources

•Documentation: https://developers.lottiefiles.com/docs/dotlottie-player
•State Machine Guide: https://github.com/LottieFiles/dotlottie-web/wiki/dotLottie-State-Machine-Guide
•GitHub: https://github.com/LottieFiles/dotlottie-web
•dotLottie 2.0 Spec: https://dotlottie.io/spec/2.0/
•Create .lottie files: https://lottiefiles.com or https://creators.lottiefiles.com

dotLottie Implementation Guidelines

Package Selection

Use @lottiefiles/dotlottie-web when:

Use @lottiefiles/dotlottie-react when:

Installation

Basic Implementation

Vanilla JavaScript

React

React with Instance Control

.lottie vs .json

Web Workers (Recommended for Performance)

Basic Worker Usage

Worker Grouping (Multiple Animations)

When to Use Workers

React with Workers

State Machines (Interactivity)

State Machine Events

Theming with Slots

Dynamic Slot Overriding

Markers & Segments

Playing Specific Segments

Getting Markers

Event Handling

Performance Best Practices

1. Use Web Workers for Complex Animations

2. Lazy Load Animations

3. Auto-Freeze is Enabled by Default

4. Device Pixel Ratio

5. Clean Up (Vanilla JS only)

6. Frame Interpolation Control

Multi-Animation Files

Canvas Sizing

Auto-Resize to Container

Common Patterns

Play on Hover

Play on Click (Once)

Scrub with Scroll

Loading States (React)

Responsive Animation

Debugging

Error Handling

SSR / Next.js Considerations

Resources

Use `@lottiefiles/dotlottie-web` when:

Use `@lottiefiles/dotlottie-react` when: