Defending Light Mode


Defending Light Mode

October 27, 2023
Estimated reading time: 4 minutes
Tags: a11y health opinion
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It's common to see programmers' terminals and text editors with colored text on dark backgrounds, and since operating systems allow for system-wide dark mode, even more so.

I won't say that the Dark vs. Light matter is a debate like vim vs. emacs or tabs vs. spaces because most have already chosen the dark side. But is dark mode really the ideal choice for you?

I don't intend to demonize dark mode by any means, but I want to give you the opportunity to choose which option is better for you.

How Your Eyes Work

Put simply, your eyes gather incoming light, and the optic nerve converts it into electrical signals that your brain can understand. To help the nerve work better, your eye adjusts the pupil to regulate the amount of light it receives. In summary, what strains your eyes the most is:

  1. Receiving too much light.
  2. Receiving too little light.
  3. Constantly making the pupil open and close.

Physical Workspace

Before we dive into the color of your virtual workspace, let's consider your real environment. According to workplace safety standards, your workspace should be clean, well-ventilated, and well-lit, without windows or lights causing glare on your monitor.

You should opt for light mode in any of these cases:

  • Your workspace is well-lit.
  • You work outdoors or in a place with plenty of natural light.
  • You work in a location with many light sources.

Light mode reduces screen glare and integrates better with a well-lit environment.

The brightness of your monitor helps mimic the outdoor brightness for a more natural reading experience. The main complaint of dark mode users compared to those who use light mode is that when sharing their screen, they experience a flash on their faces when viewing the light screen. However, this effect occurs because:

  1. Your eyes need to adjust to the new light source.
  2. Your monitor is set to a higher brightness for dark mode.

The first and second points on our list of eye strain factors can be resolved if your screen is adjusted to match the brightness of your environment.

Other Applications You Use

Even if you set dark mode for your entire system, there are often other applications that display content in white, such as web pages or PDF documents. While you can "force" a dark mode on these elements, the result may not be very attractive. If your job involves formatting these websites or documents, it's not logical to change the colors.

Alternating between something light and something dark strains the eyes more.

Switching between a white document and a continuously black screen is a tremendous effort for your eyes, as they need to adjust the pupil with each change.

You should go for light mode in any of these cases:

  • You work on formatting websites or documents with a light background.
  • The tools you regularly use only have a light mode (e.g., Jira, Bitbucket, Google Suite, etc.).

The third point on the list of eye strain factors is resolved by avoiding the contrast between looking at something very light and something very dark.

Light β‰  White

When I talk about a light theme, I don't mean using a white background. In fact, I prefer to use a light gray background in my applications and highlight the current line in white. This gives me a more natural effect, as if I were looking at paper.

There are many light mode themes available in all applications that support it. One of the most well-known is Solarized, but I prefer PaperColor Light. Find the one that suits you best.

Personal Experience

I have had astigmatism for some time, and recently, a neuritis in one eye left my vision impaired. I get tired more easily than before, and I need to take care of my eyes.

I used to use dark mode because I assumed it was better for the eyes. It was said to be less tiring because it emits less light towards the eyes. But I didn't stop to analyze what was really best for me until a few years ago.

Personally, light mode is better for me. Decide what's best for you.

I admit that in low-light situations, such as using my phone at night, a light theme can be blinding. My solution is to stop using any devices at night; I sleep better that way.

But when using a dark theme (and believe me, I've tried them), I see the text as excessively bright, like neon lights. Not to mention that having a black editor side by side with a white web page gives me a headache.


I don't intend for you to read this article and switch to the light side, but rather to analyze your needs and what's best for your health. It took me a while to realize this and I assumed many things that I read were true.