Legibility vs. Readability: The Difference Every Designer Should Know

Let's clear up two terms that often get mixed up: legibility and readability. They're related but not the same — and knowing the difference will level up your UX design instantly.

What is legibility?

Legibility is about character clarity. Can users distinguish one letter from another? Is your "rn" accidentally looking like an "m"? Legibility focuses on the visual design of individual characters.

Think of it as: Can I see this clearly?

What is readability?

Readability is about comprehension. How easy is it to read and understand the text as a whole? This includes word choice, sentence length, formatting, and overall flow.

Think of it as: Can I understand this easily?

Why both matter in UX:

You need legible text so users can decode what's on the screen.

You need readable text so users can understand it without working hard.

When you optimize for both:

✅ Users experience less fatigue

✅ Satisfaction increases

✅ Your product feels more intuitive

The research backs this up:

Studies show that thoughtful text design — combining legibility and readability — reduces cognitive load and improves user perception. In other words: better text = happier users.

Here's the designer edge:

In a crowded market, attention to these details sets you apart. Products with clear, understandable text don't just look better — they perform better.

Over to you: Do you check readability when designing content? What's your go-to tool?

Bonus insight: The Flesch Reading Ease formula (from 1948!) is still widely used to measure text difficulty. It scores text from 0-100, with higher scores meaning easier reading.

Takeaway:

Make your text legible so users can see it. Make it readable so they can understand it. Master both, and you'll create experiences that truly connect.