Accessibility and fonts
Simplicity is the ultimate sophistication.
— Leonardo da Vinci

When we think about fonts and inclusive design, we can sometimes jump to conclusions based on intuition, instead of asking or testing features with anyone who actually has a disability. The problem with this is that you may end up excluding the very people you are trying to include.
Let’s begin by considering what the actual goal is: we want as many people as possible to be able to comfortably read the content that we’ve created. In order to accomplish this, we need to consider what variables actually help people read more comfortably and what barriers might be in place that prevent easy reading.
Over the past 150+ years, many, many studies have been done on how people read best. Every time, studies show that people read most comfortably when the letterforms are familiar, when there are short line lengths, when there is proper spacing and when each character has a very distinct form.
People are more comfortable in familiar territory
People recognize most any fonts that they see most often. Topping the charts are almost always, fonts used in computer operating systems. In screen contexts, most computers, buttons and interactive elements (UI) are set in sans-serif. And print, newspapers, magazines and books are set in plain serif fonts.
As welcome as new ideas are, changing what people are used to seeing adds barriers to reading. If you want to find fonts that are reader friendly, even for dyslexic readers, common fonts are best.
You can stay reasonably safe with these:
- Sans-serif: Arial, Helvetica, Verdana,
- Serif: Times New Roman
Legibility improves when letters look visibly different
That said, there are some things to double check. Characters like, I, l and 1, or O and 0, or O and C need to look different enough from one another.
Words like “Illusion”, can be tricky to read when uppercase I and lowercase l look exactly the same.
Letters need adequate spacing
When some letters are too close together “ol” can look the same as “d” or “rn” can look the same as “m”. This can become problematic in distinguishing words like, “corn” vs “com” or “cod” vs “cool”. When you need your text to be clear and easy to read, you need to make sure every aspect is clear.
Fonts need enough contrast and weight
Anyone with low vision, will need strong contrast and font weights that aren’t too thin. This includes anyone looking at their phone screens outside on a sunny day, people who just entered a dark room from a bright one, people with blurry vision in the mornings and anyone with impaired vision. Hairline fonts are too thin to read comfortably. There is no specific rule for this that applies to all typefaces. Every typeface is different so you’ll need to use your best judgement.
Contrast matters as well. Gray lettering on a gray background may not be clear enough to read easily.
Shorten the width of your paragraphs
When you visit your website only on a phone or a small tablet, you may think it’s fine to have paragraphs that span across the entire screen width. The issue is that those aren’t the only devices people use to browse the internet. Visitors also use their 4K smart TVs or retina screens or laptops. When paragraphs are over 70 characters long, people have difficulty tracking.
Tracking happens when you finish reading a line and need to move to the next line. You need to move your focus from the far right hand side of the screen all the way over to the left. If that’s a long distance then you may lose your place. Shorter paragraph widths help make that tracking much easier.
Curb-cut phenomenon
If you aren’t familiar with it, the curb-cut phenomenon happened when cities changed street corners to ramp down instead of keeping the regular curb. This helped people in wheelchairs cross the street more safely and easily, but it also helped parents pushing strollers, people pushing grocery carts, and everyone using any wheeled transportation.
Having fonts that are easy to read on your website not only helps people with low vision or dyslexia, it helps everyone read your work.
But don’t just take my word for it. Here is further reading on this topic:
A Guide to Understanding What Makes a Typeface Accessible
It’s About Legibility