Readability vs. Legibility

What is readability?

Readability refers to how easy it is for someone to read and understand a given piece of writing. Children's books are an example of text with high readability. They tend to use shorter sentence lengths and simpler, more common vocabulary. A graduate school textbook, on the other hand, has low readability. These dense compositions contain long, complicated sentences and complex jargon. Reading one for a few minutes is likely to give you a headache.

Researchers measure readability by the years of education needed to understand a text. For instance, if someone writes a novel at a 5th-grade level, you would need that level of education to understand it. In the United States, the average adult reads at an 8th-grade level, so that is a common target for mass communications. You can check the readability of your text with Hemingway's free online readability checker.

What is legibility?

Legibility refers to how easy it is to distinguish the individual letters and words used in a piece of writing. It refers only to the visual aspects of the text and not its content. Highway signs are an example of text with high legibility. The letters are printed in a clear, straightforward font with adequate space between each character. It's easy for someone to read the letters without much effort.

For an example of low legibility in design, think of a note written with poor handwriting. You might struggle to tell the different letters apart and decipher what it's saying. Even if you're writing a simple message with high readability, if your writing is not legible, users won't be able to understand it. For this reason, legibility is an essential element of UX design.

Why are readability and legibility important for effective communication?

At its core, writing is about conveying a message to another person. You might be trying to persuade them to change their perspective, or you might be giving them an update on your life. No matter what you're trying to write, if the other person can't understand you, then you haven't been successful.

Imagine spending hours composing a letter to a friend and then finding out that they couldn't understand it. It could happen for two different reasons:

1. If your readability is too low, they might get confused by long, winding sentences or tricky vocabulary.

2. If your legibility is too poor, they can't make out the font you chose or understand your handwriting.

The most effective copy has both high readability and high legibility. While the two factors refer to different aspects of your text, they're both essential.

How to improve readability: tips and tricks

1. Use a readability checker to understand the current grade level of your text. Hemingway's free online readability checker is the best tool for the job. It provides both an overall readability score of your text and also highlights individual sentences that are hard to read.
2. Wherever possible, replace complicated terms or jargon with simpler synonyms. Use common, everyday words that anyone can understand.
3. Break up long, complicated sentences into shorter, simpler sentences that focus on one idea each.

How to improve the legibility of your writing and improve UX design

1. Choose a clear, legible sans-serif font like Arial, Helvetica, Georgia, or Open Sans. Sans-serif fonts (which don't include extra accents around letters) are often best. You can test the legibility of a font by reducing its size or squinting your eyes. If you can still read it without difficulty, it likely has high legibility.
2. Examine the letter spacing or "tracking" of your text. Ensure there is enough space between each character for clear differentiation. When letters are too close together, they can be harder to read.
3. Ensure your font size is large enough for readers to see without difficulty. Consider how far away someone will be when reading your text. Also, keep in mind that some readers have different levels of eyesight, so they may need larger fonts for accessibility.
4. Ensure your text and background colors have a significant level of contrast. For example, use dark text over lighter background colors or vice versa.

FAQ

What is the difference between readability and legibility?

Readability refers to how easy it is for a reader to understand the content within a piece of writing. Legibility is how easy it is to read text. The font choice, letter spacing, size, and contrast all affect it.

How do readability and legibility affect user experience (UX) design?

Before moving to the UX phase, it is important to make your text as clear and legible as possible. Once you start laying it out, consider your target audience. Your design choices (font, color, typography, etc.) must fit that demographic. Consider where the design will live, how users will experience the design, and any accessibility concerns.

What are the best fonts to increase legibility?

Choose simple, sans-serif fonts such as Arial, Open Sans, Helvetica, Inter, or Lato. These fonts tend to have the best performance when rendered at low resolutions or on computer screens.

Why is legibility important in typography?

Legibility is the most important consideration for typography. While visual appeal is also essential for attracting readers, you must ensure they are able to read and comprehend the text. If readers are unable to make out what the text says, it no longer serves its purpose.

Is serif or sans-serif better for readability?

While there is no one-size-fits-all solution, in general, sans-serif fonts tend to have better readability. This is because the more minute aspects of a serif font may not render as well at low resolutions or on computer screens. It is important to consider your audience and the location where the text will appear when choosing the best font.

Are readability and legibility important for SEO?

Yes, readability and legibility are both crucial elements of SEO performance. To achieve great SEO, you must write informative content that readers find easy to understand. If they struggle to comprehend the text or find it difficult to read, your bounce rate and page performance will suffer.