When I see a flier posted in the office kitchen telling me how to clean up after myself, I just kind of lose it a little.

But it’s not because of the message. It’s the fact that it’s typed in Comic Sans that really sends me into an inconsolable rage.

Everyone knows that Comic Sans is the worst font! I only write in Arial. And in school, my teachers insisted on Times New Roman.

So we all have strong opinions about what font to use and whether they should have those stylistic serifs. Those decisions may seem inconsequential, but they’re more important than you think. Sometimes there really are good reasons to use one font over another.

But there are no circumstances in which Comic Sans is the acceptable first choice. Right? Well, here’s what researchers say are the best fonts for different situations. [♪ INTRO] Maybe the most hotly debated text features around are serifs.

Those are the extra little tips and feet that stick out from letters in certain fonts. The fonts that don’t have them are called sans serif. For example, probably the best-known serif font is Times New Roman, and for sans serif it’s Arial.

These two fonts are constantly pitted against each other in the ultimate battle of the fonts. One that, inevitably, researchers have quantified. In a study from Wichita State University, researchers asked people to fill out a questionnaire and rank fonts based on their preferences and perceived readability on a computer screen.

Both fonts were scored on a scale from 1, which is not at all readable, to 7, which is very easy to read. And Arial was ranked on top. The participants of this study ranked a passage typed in Times New Roman font to be on average 0.4 points more difficult to read.

So not a jaw-dropping effect, but it’s something. And it aligns with common lore that sans serif fonts are preferable on a screen, while serif fonts are preferable in print. But, oddly enough, when the same people were asked what font they use on their own computers, over half of them defaulted to Times New Roman.

And that’s probably because there doesn’t seem to be any real difference between how readable serif and sans serif fonts are for general reading. This holds true across multiple languages and even multiple alphabets. Studies on both the Latin alphabet, which is used to write in English and many other languages, and the Cyrillic alphabet, which is used to write in Russian and several other languages, find no real difference in readability between serif and sans serif fonts.

The Cyrillic alphabet-focused study, published as a collaboration between Russia- and US-based researchers, assessed 238 participants’ reading speed and comprehension for serif and sans serif texts. They had everyone read a history of neurology in Russia and collected data on how many words per minute they could read comfortably. The participants then took a short quiz to see how much information they retained from the text when reading serif versus sans serif fonts.

And there were no significant differences in reading speed or comprehension, so it’s all pretty much a wash. But if you’re a die hard serif stan, you probably think they won’t get their fair testing conditions until the study investigates print rather than computer screen layouts. After all, word on the street is that serifs are easier to read on a piece of paper.

So to test those conditions, researchers in Austria compared German text in serif Times New Roman and sans serif Helvetica fonts printed out in paperback book format. Just like the Cyrillic study, they assessed reading speed. But this investigation also assessed how long it took to read the entire passage, and how many reading errors the participants made along the way.

The results showed… absolutely no difference between serif and sans serif fonts. Sorry Times New Roman nerds. Participants made the same number of errors on average when reading either font and had no significant difference between them in terms of reading speed or reading time.

So, preferences aside, serifs don’t seem to matter when it comes to general reading. But there are situations where font makes a difference, like behind the wheel. You probably don’t think about it much, but there’s a shocking amount of reading to do while you’re driving.

And no, I’m not talking about distracted driving from the text coming in on your phone! Don’t look at those, by the way. I’m talking about road signs.

Depending on where you’re cruising, there could be road signs literally coming at you a mile a minute! And a huge number of those signs are written in sans serif fonts. The industry standard font has been serif-free since the 1950’s, when Highway Gothic made its debut, and although a newer font called Clearview is starting to replace it, Clearview is sans serif too.

So it’s no surprise that researchers have studied whether sans serif fonts specifically are better for that purpose. In matters of life or death, like seeing a sign that says “Stop,” “One Way,” or “Do Not Enter,” it’s pretty important to make them as legible as possible. And if you’re a lead foot on the highway, you’re going to want to read road signs from far away so you have time to respond.

In those cases, there’s some data to support the ubiquity of sans serif fonts on road signs. One study, published in the Interdisciplinary Journal of Signage and Wayfinding, simulated large font road signs with 33 different fonts, including both serifs and sans serifs. And can we just take a moment to appreciate that there’s a whole journal for signage and wayfinding?

They had 64 people from the ages of 19 to 87 read the signs on a computer screen across the room. To figure out how far away a specific font could be read from, the font would start out at 5 millimeters tall and get bigger until the participant could read the words. Then, the researchers used the information of how tall the letters were to calculate the real-life distance that it translated to.

So if the participant could read words in Arial on the screen at 35 mm tall, that would suggest that they could read a road sign with 25 cm tall Arial font from 106 meters away. Once they had that real life estimate, they ranked the 33 fonts based on how far away the average person could read them on a road sign. And the top two fonts for distance reading were called Gill Sans and Avenir Medium, which are both sans serif!

So that, along with the preference for sans serif fonts described in general reading, might help explain why so many road signs use sans serif fonts. But, while sans serif fonts are slightly more legible at a distance, there was no significant difference between serif and sans serif fonts overall. Now, don’t get me wrong, some fonts are definitely better than others.

Like, no one is saying we can throw Wingdings onto speed limit signs. But a lot of them are interchangeably readable, and whether or not they had serifs doesn’t seem to really matter. But if serifs aren’t the deciding factor for distance reading, there are still other factors that help explain the ranking.

Things like font size are more important. Also, bold fonts tend to be more legible. And printing in all caps seemed to help distance reading too, which might explain why STOP signs have to be shouting at you.

But, again, it’s not really the serifs making the font more or less legible on a road sign. Probably because they’re insignificant compared to the rest of the letter. One admittedly small study published in the journal Vision Research even found that you may be able to read serif fonts faster than sans serif fonts at a distance.

The authors suggested that this could be because they make letters more distinct from each other and they draw the eye forward to help you read faster. But distance reading isn’t the only kind of in-car reading people are up to these days. With newer, fancier driving machines come digital display screens.

These can display your driving directions, or just help you figure out what sick tune you’re listening to. We’ve already said that studies show there’s no difference between serif and sans serif fonts when reading on a screen, so let’s focus on factors that do seem to help you read these displays. A study called “The Great Typography Bake-Off,” because researchers can’t help themselves, compared eight sans serif fonts and found that those with more open shapes and contours were easier to read at a glance than those that were smooshed together.

And they also found an age effect. In this study, 75 year olds took 38% longer to read the screen than 35 year olds. Which brings us to another crucial factor in font selection… So let’s address the elephant in the room.

Here’s what fonts are best when your vision is deteriorating. One reason your vision might get worse is age-related macular degeneration. That’s what happens when part of your eye called the macula gets thinner or scarred with age, and causes your vision to become blurry.

It can even cause blind spots in your field of vision. It’s also the leading cause of vision loss in people over the age of 50, so understanding how it affects legibility in written texts really matters for a lot of people. A study published in the “Canadian Journal of Ophthalmology” recruited 24 participants around 82 years old with macular degeneration in both eyes for a series of reading tests.

They made sure the participants had no other cognitive or other eye conditions, which means that whatever conclusions they came to would most likely be the result of macular degeneration specifically. The researchers had the participants go through four reading charts, each in a different popular font. Two of them had serifs and two of them didn’t.

And just like the chart with the big E that you know from the eye doctor’s office, the font size got smaller and smaller as they moved down the chart. The participants could read the smallest words on the chart printed in Courier font, which has serifs. And the worst performance was on the Arial chart, which is a sans serif font.

So the default sans serif font was tougher for people with age-related macular degeneration to read. And literally after reading that line, we switched our teleprompter front from Arial to Courier, and I’m lovin’ it! And the conclusion that might knock my grade school teacher right off their chair is that Courier even beat Times New Roman!

Which means there’s something about Courier that makes it easier to read under these circumstances, aside from the fact that it has serifs. And that thing might be spacing between the letters. Courier is a wider font with more space between letters than Times New Roman.

So it’s easier for people with age-related macular degeneration to read the letters at smaller sizes. But age isn’t the only reason you might experience vision degeneration. Another study out of Denmark assessed 19 people with autosomal dominant optic atrophy.

This condition weakens your vision by deteriorating the optic nerves. Just like the last study, this one compared four modifications of one base font, where two had serifs and two didn’t. And they found that people with this kind of optic degeneration also read serif fonts better than sans serif fonts.

But again, it’s more than just the serifs. It’s how the text is presented. This study concluded that fonts with serifs are easier to read when each part of the letter has a uniform width.

And you know what font doesn’t do that? You guessed it: Times New Roman. I know Times New Roman has a special place in some of your hearts.

But for this specific population of people with this eye condition, it’s probably harder to parse. That means that while some people have an easier time reading certain fonts, others can have a harder time reading the exact same ones. And one of those cases is dyslexia, which about 10% of people have.

Someone diagnosed with dyslexia might find certain fonts more difficult to read than someone else who doesn’t. Now, you may also have heard of some fonts that have been specifically designed for people with dyslexia. Fonts like Dyslexie and OpenDyslexic were created to increase readability for dyslexic people.

Since dyslexia makes it harder for people to distinguish letters with similar shapes, the idea with these fonts is that letters like b and d are not mirror images of each other, so they’d get mixed up less often when you’re reading them. So researchers put one of these fonts to the test. And the results were… kind of underwhelming.

To investigate how dyslexia factors into font readability, a study out of Barcelona used eye-tracking software to test reading speed among people diagnosed with dyslexia. In a comparison of 12 different fonts, including OpenDyslexic, they found that sans serif fonts were easier to read. Or at least, they didn’t require focused gaze for as long as serif fonts did.

They didn’t find a huge difference in reading time between all the fonts, but they did find another factor that increased gaze focus even more. Italics really seemed to increase reading time and decrease readability for this group. That was a main finding.

Not that OpenDyslexic made reading easier. In fact, OpenDyslexic didn’t even make reading easier than plain old sans serif options like Verdana. Studies in Spanish and in Dutch have also found the effects of these special fonts to be kind of disappointing.

For instance, they don’t lead to faster reading times among dyslexic participants as compared to Arial. And it might be for the same reason that participants in other studies found certain fonts better or worse. Sometimes, you just need enough space between the letters.

A lack of space around each letter is called “visual crowding,” and it’s been found to make reading harder for children in Spanish, French, and Italian. One collaborative study out of Italy and France even found that having enough space between letters had as much impact on students’ reading speed as an entire year of reading practice, within a single testing session. So, to keep it less crowded, the current recommendation of the British Dyslexia Association is to use sans serif fonts like Arial or Comic Sans.

Yeah, you heard me. Comic Sans is one of the recommended font for dyslexic readers. So it might be time to put down the Comic Sans pitchforks.

There’s no one-size-fits-all solution in the battle of the fonts. A dyslexic person might find Comic Sans easier to read while someone with vision deterioration could find the lack of serifs in that same font harder to see. But sometimes, we’re just being picky when a serif here and there doesn’t make a difference at all.

So give your most hated font a little bit of slack, okay? Unless it’s Wingdings. Thanks for watching this episode of SciShow.

And if it got you all curious about all things typographical, you can check out our recent episode about what science has to say about the best kinds of keyboards. And after watching that video, you’ll have all the scientific knowledge that you need to finally write that novel you’ve been putting off. Go on, you can do it!

I believe in you! [♪ OUTRO]