A Guide to Webfonts: What They Are, How to Use Them, and Best Practices

So You Want to Add a Font?

Fonts are more than just letters on a screen—they’re a vital part of your website’s design and branding. The right font sets the tone for your site, conveys your brand identity, and can even influence how users perceive your content. Whether you’re aiming for sleek minimalism, playful creativity, or bold professionalism, fonts play a starring role in making a website memorable.

But as essential as fonts are, they also come with technical considerations that can impact your website’s performance. Let’s dive into what webfonts are, how to use them, and some best practices to keep your site looking great and running smoothly.

What Are Webfonts?

Webfonts are fonts downloaded by a user’s browser when they visit your website. Unlike standard system fonts (like Arial or Times New Roman), webfonts are hosted on a server and can be custom-designed to align with your brand’s identity. Webfonts allow you to create visually unique designs that stand out from the crowd, making them a must-have for modern web design.

Why Font File Size Matters

Font files can be surprisingly large, especially if you’re using multiple styles (like bold, italic, or light weights). Large font files can slow down your website, increasing load times and frustrating visitors. This is especially critical on mobile devices or slower internet connections.

To keep your site fast:

• Only load the styles and weights you need.
• Use modern, compressed formats like WOFF2, which are smaller than older formats like TTF.

Browser Support for Font Files

Most modern browsers support webfonts, but the type of font file you use matters. Here's a quick rundown of common formats and their compatibility:

• WOFF2: The most modern format with the best compression (widely supported).
• WOFF: Older but still widely supported.
• TTF/OTF: Legacy formats; larger and less optimized for the web.
• EOT: Specific to older versions of Internet Explorer.

Using multiple formats in a font stack ensures compatibility across browsers.

The @font-face Rule

The @font-face rule is a CSS declaration that lets you load custom fonts. Here’s an example:

@font-face {
  font-family: 'MyFont';
  src: url('/fonts/myfont.woff2') format('woff2'),
       url('/fonts/myfont.woff') format('woff');
  font-weight: 400; /* Regular */
  font-style: normal;
}

• font-family: The name you’ll use in your CSS.
• src: The location(s) of your font file and its format.
• font-weight & font-style: Define the specific weight (e.g., bold) and style (e.g., italic).

When using multiple styles (like bold or italic), declare them separately with unique weight and style values.

Should You Host Fonts Yourself?

There are two main ways to use webfonts:

1. Host them yourself (self-hosting).
2. Use a third-party service like Google Fonts.

Benefits of Hosting Your Own Fonts:

• Control: You can optimize and compress files for your specific needs.
• Privacy: Avoid third-party tracking (especially important for GDPR compliance).
• Fewer External Requests: Reduce dependencies on external services, improving performance.

Free and Open-Source Fonts

If you’re looking for quality fonts without the price tag, these resources have you covered:

• Google Fonts: A massive library of free, high-quality fonts.
• Fontshare: Free, professional-grade fonts.
• The League of Moveable Type: Open-source fonts for creative projects.

Font Swapping and Performance

When webfonts are loading, browsers often show a fallback font until the custom font is ready. This is called font swapping.

In CSS, the font-display property lets you control this behavior:

@font-face {
  font-family: 'MyFont';
  src: url('/fonts/myfont.woff2') format('woff2');
  font-display: swap;
}

• swap: Shows fallback text immediately, then swaps in the webfont once loaded.
• optional: Skips loading the font if it’s slow, favoring performance.

Font swapping reduces performance bottlenecks, but you might notice a "flash of unstyled text" (FOUT). To minimize this, optimize your font files and preload key assets.

Preloading Fonts for Performance

Preloading key resources, like fonts, helps improve page load times by telling the browser to prioritize them. Here’s an example snippet:

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

This tells the browser to download the font early, reducing delays. For stylesheets, here’s a common performance hack:

<link
  rel="preload" 
  href="/styles/main.css"
  as="style"
  onload="this.onload=null;this.rel='stylesheet'"
/>
<noscript><link rel="stylesheet" href="/styles/main.css" /></noscript>

How It Works:

• The rel="preload" fetches the stylesheet earlier in the loading process.
• The onload attribute swaps rel to stylesheet once it’s ready, ensuring it applies to the page.
• The <noscript> tag provides a fallback for users without JavaScript enabled.

This approach boosts perceived performance by making styles available sooner.

Best Practices for Webfonts

1. Use Modern Formats: Stick with WOFF2 for the best compression and performance.
2. Minimize File Sizes: Only load the weights and styles you need.
3. Leverage Preloading: Use rel="preload" to prioritize key fonts.
4. Optimize Swapping: Set font-display: swap to reduce delays in displaying text.
5. Host Locally if Possible: Self-host fonts for better control and privacy.

Fonts are powerful tools for branding and design, but they also come with technical trade-offs. By understanding how to use them effectively and adopting best practices, you can create a visually stunning website that also loads quickly and performs well.

Disclaimer: This article provides general guidance on webfonts. Always test your implementation to ensure compatibility, performance, and accessibility for your specific audience.