A Moment of Science

Seeing Yellow

Why is yellow still the most popular highlighter color?

a hand holding a yellow highlighter

Photo: J. M. Rosenfeld

Our eyes are most sensitive to yellow and green, so they're the easiest colors for us to see, even when we're not looking directly at them.

Walk into almost any office supply store, and you’ll see highlighters in almost every color imaginable.

Why is yellow still the most popular highlighter color? Because, even though yellow might not be your favorite color, your eyes naturally see the color yellow much more easily than, say, blue or red.

Wavelengths Of Color

The reasons for this have to do with the wavelengths of different colors. Think of a rainbow, the range of colors of visible light. It goes from red, the color with the longest wavelength, through orange, yellow, green, blue, and indigo to violet, the color with the shortest wavelength. Yellow and green are right in the middle of the spectrum’s wavelengths.

Our eyes are most sensitive to yellow and green, so they’re the easiest colors for us to see, even when we’re not looking directly at them. And even people with red-green color blindness can still see yellow, that’s why it’s the most popular color for highlighters.

Noticing Change

If we notice yellow and green more quickly than other colors, then why are stop signs and most emergency vehicles painted red?

That’s a good question! The choice of red has more to do with tradition than visibility. In fact, many communities have started to paint their fire equipment and ambulances a very bright yellowish-green, which helps motorists to see them coming, and get out of their way more quickly.

  • Pingback: Monkey See, In Full Color | A Moment of Science - Indiana Public Media

  • http://www.facebook.com/profile.php?id=30400145 Charles W. Wigell

    I heard a few times in college that when you used a blue highlighter it was shown to give you better recall later on. So now I only use blue.

  • http://profiles.google.com/dpoppeli dimitri poppeliers

    That’s a nice scientific explanation but the other reason would be that other colors (red, blue, etc) are “darker” making the text difficult to read due to lower contrast.

Stay Connected

What is RSS? RSS makes it possible to subscribe to a website's updates instead of visiting it by delivering new posts to your RSS reader automatically. Choose to receive some or all of the updates from A Moment of Science:

Support for Indiana Public Media Comes From

About A Moment of Science

Search A Moment of Science