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Re: Is there any industry agreed viewport to verify 1.4.4: Resize Text

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From: Steve Green
Date: Nov 20, 2023 11:44PM

The physical size of the screen does not matter - it's the screen resolution that matters, and also the scaling factor in Display Settings.

My view is that we should test using screen sizes that users will have. 1920x1080px seems reasonable. Higher resolution screens are available, but I don't think they are common. If you have a screen of that size, you can also test at any lower resolution.

The scaling factor isn't so obvious. It only became an issue when laptops with physically small screens started to have high resolution. It's not an issue for me because I always use a large screen (usually 27"), but my inclination would be to always use a scaling factor of 100% regardless of screen size. And why would testing be done on tiny 14" screens? That's inefficient and more prone to error than a large screen. Testers (and everyone else) should insist on having the equipment they need to do the job properly and should not just accept what they are given.

You obviously can't test at every possible browser window size, so I typically test thoroughly at a width of 1280px because I'm using that for Reflow. Then I look at how the layout changes as I increase the width to 1920px. I test at that width and maybe at intermediate widths if it looks like there might be issues.

I also check what happens when the window width is reduced all the way down to then the mobile layout kicks in. This isn't a comprehensive test, but it's just to get an understanding of the design and see if anything nasty is likely.

Steve Green
Managing Director
Test Partners Ltd