February 6, 2025
Web font optimization is an essential aspect of improving website performance. With users demanding faster load times and a smoother browsing experience, optimizing fonts can significantly reduce page load times and improve the performance of ads. Faster pages lead to better user experiences and improved ad delivery. This article will guide you through various strategies to optimize web fonts, reducing costs and increasing revenue through more efficient ad performance.
The first step in optimizing web fonts is deciding whether to host them yourself or use a third-party provider like Google Fonts. Each option has its benefits and challenges:
The more fonts you load, the more data the browser needs to fetch, and the longer it takes to display content. Reducing the number of fonts you use can have a significant impact on performance.
Large font files can slow down your website significantly. Reducing the size of these files is crucial for performance.
Consider a scenario where you only need Latin characters for your website. By creating a subset that includes just those characters, you can reduce the font file size by removing characters you don’t need.
glyphhanger --subset=font.woff2 --format=woff2 --LATIN
This ensures that only the necessary character set is included, reducing the file size.
One of the most powerful strategies for reducing font file sizes is using variable fonts. These fonts allow multiple styles (e.g., regular, bold, italic) to be combined into a single file. While this reduces the number of font files needed, there’s still a significant amount of optimization you can do by eliminating unused font axes, such as weights and widths.
You can use font editing tools like the Axis Editor or Slice (from Source Foundry) to eliminate unnecessary weights and widths.
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Let’s say you’re using Source Sans Pro as a variable font, and you only need the regular and bold weights, with a normal width. Instead of using the entire variable font file, you can remove the intermediate weights and widths.
This 22% reduction in file size can make a significant difference in performance.
How fonts are displayed and loaded can impact both performance and user experience. Here are the main strategies:
The font-display property controls how a font is rendered while it’s loading. The most common values are:
Use the <link rel="preload"> tag to prioritize font loading. This allows the browser to fetch the font earlier in the loading process, improving render times.
<link
rel="preload"
href="/fonts/myfont.woff2"
as="font"
type="font/woff2"
crossorigin="anonymous">
Cumulative Layout Shift (CLS) is a metric that tracks unexpected layout shifts during page load. To minimize CLS caused by fonts:
Optimizing web fonts is a critical step in improving both user experience and ad performance. By choosing the right hosting strategy, reducing font file sizes, and carefully managing font weights and widths, you can dramatically improve page load times. These optimizations not only make your site faster, but they also improve ad performance, leading to better revenue and lower costs.
Whether you’re developing a website or managing ads, implementing these font optimization techniques will help you stay ahead in the competitive digital space.
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