Browser Support: The Two Metrics That Count

Published on Jan 27, 2009 (updated Oct 17, 2024), filed under development. (Share this post, e.g., on Mastodon.)

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There are two things that matter to determine what user agents—browsers—to support on a given site: First, what popularity (percentage of market) makes a browser important to support? Second, what browsers pass that threshold?

This may sound completely obvious, but it still requires a meiertesque post, because occasionally, other variables are thrown at the decision what browsers to support. For example, some consider browser beta versions or niche operating systems, use “grades” or “tiers,” or miss options like graceful degradation and progressive enhancement.

Still, what matters is browser popularity (in your market segment, if you like at least one level of complexity), and your choice of what percentage makes a browser worth testing for. Supporting browsers is as simple as that; in a corporate environment, a list of browsers to be supported that gets updated each quarter is usually enough.

Here’s what I typically do: For an existing site, I have a look at its server logs and statistics and compare these with competitors as well as my own data. If the site is new I’d consider public metrics. Then I’m likely to set a support threshold of 1% and make sure that the site works (looks and behaves about the same, that is) in all browsers that are used by that 1% of visitors. Although they have nothing to do with what browsers to support, graceful degradation and progressive enhancement are then part of the development toolbox.

About Me

I’m Jens (long: Jens Oliver Meiert), and I’m an engineering lead, guerrilla philosopher, and indie publisher. I’ve worked as a technical lead and engineering manager at various companies (e.g., Google); I’m an active web and tool developer (code optimization, digital defense), a contributor to web standards (like HTML, CSS, WCAG), and a book author (O’Reilly, Frontend Dogma).

I love trying things—in web development and engineering management, but also in politics and philosophy, where I hold to one idea in particular: that we can only be well if we take good care of everyone. Here on meiert.com I talk about some of my perspectives and experiences. (Interpret charitably but be critical—and share feedback and advice that makes my work better.)