Addressing Accessibility Concerns With Using Fluid Type — Smashing Magazine

You may already be familiar with the CSS clamp() function. You may even be using it to fluidly scale a font size based on the browser viewport. Adrian Bece demonstrated the concept in another Smashing Magazine article just last year. It’s a clever CSS “trick” that has been floating around for a while.

But if you’ve used the clamp()-based fluid type technique yourself, then you may have also run into articles that offer a warning about it. For example, Adrian mentions this in his article:

“It’s important to reiterate that using rem values doesn’t automagically make fluid typography accessible for all users; it only allows the font sizes to respond to user font preferences. Using the CSS clamp function in combination with the viewport units to achieve fluid sizing introduces another set of drawbacks that we need to consider.”

Here’s Una Kravets with a few words about it on web.dev:

“Limiting how large text can get with max() or clamp() can cause a WCAG failure under 1.4.4 Resize text (AA), because a...