Optimizing Fonts in Next.js Applications

Optimizing fonts in Next.js applications involves several strategies to improve the loading experience. These strategies focus on reducing latency, minimizing layout shifts, and enhancing overall performance.

Eliminate External Network Requests

Serving fonts locally from your domain can significantly reduce the time it takes for fonts to load. This approach eliminates the need for external network requests, which can slow down your application.

import localFont from '../fonts/local-font.woff2';

const MyApp = () => {
  return (

); };

Preloading Fonts

Preloading fonts allows the browser to schedule downloading the font early, which can improve the loading experience. You can use the rel attribute to specify the preload link type.

<link rel="preload" as="font" href="/fonts/font.woff2" crossorigin="anonymous">

Use the CSS size-adjust Property

The CSS size-adjust property can help reduce layout shifts when switching between fonts. This property adjusts the font size based on the aspect ratio of the font.

.font {
  font-size: 16px;
  size-adjust: 100%;
}

Leveraging Next.js 13 Font System

Next.js 13 introduces a built-in font system that simplifies font optimization. This system:

• Automatically self-hosts fonts, eliminating the need for external network requests.
• Optimizes font loading, ensuring that fonts are loaded efficiently and with minimal impact on performance.
• Provides a simple API for customizing font optimization to meet your application’s specific needs.

import { Font } from 'next/font';

const myFont = Font({
  src: '../fonts/my-font.woff2',
  weight: '400',
  style: 'normal',
});

function MyApp() {
  return (

  );
}