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Dark-mode lowers power consumption on OLED devices

You can potentially save a great amount of battery if your device is using an OLED display, just by switching to a dark theme.

Most of you probably heard about light and dark themes and maybe some of you have even seen them on websites you’ve visited. Light and dark themes are getting more and more popular and choosing to add a dark theme to your website might be a better idea than you think. For many years websites have been built with light and colorful themes because it was a standard way of doing things and according to my theory probably also because most of the materials we have designed on have always been white. A long time ago we were designing newspapers and posters on white & greyish paper, later on, white paper and then on white backgrounds on the computer.

A white background color might be best on the paper since that is how it is made, but when choosing a white background on a screen you are using the maximum amount of light and therefore your screen will be using the maximum amount of power to present you the white background. In a world where we don’t have to worry about energy consumption, a white background might be perfect, but the reality is that we need to act and start rethinking the way we do things and make them more sustainable. The internet today (statistics from 2020) is measured to be such a bad polluter that if it was a country it would be the 7th worst in the world. Servers take up a massive amount of power and devices as well, but one way we can help turn it around is by lowering the consumption by using dark themes.

Light vs dark theme.

Light and dark theme might be really good looking but it also brings other advantages to the table. Studies show that some people easily read black text on a white background while others prefer white text on black background. We are all different and until recently we didn’t know that we could make reading easier for some people just by switching a background color.

Being able to switch between themes can also be used as a method to gain the trust of the visitor. Most people like when they have the power, and just by letting them choose how their visit should look like, can make them come back and prefer your website over others. It is not a sure thing, but we as people are egocentric even though we don’t want to admit we.

Why does dark mode save power on OLED?

To understand why OLED displays save power, we need to understand the basics of a display. LED displays have backlighting which means there is a constant light behind them and then the screen decides whether it should show colors or contrasts. OLED screen and build differently. OLED contains millions of individual lighted diodes and instead of using backlighting, each little diode will light when needed. So as you can imagine, when showing a pitch-black background none of the diodes will light and thereby save power. If you have a black background with white text, then only the white text will consume power.

Conclusion.

Already by July 2018, there were just above 1 billion smartphones around the world using OLED displays and now in 2021, we can only guess how high that number is. OLED has become the new standard on smartphones and therefore we see lots of potential for saving energy. Saving energy can be done as simply as setting a dark theme as standard and then letting your users or visitors decide if they want to use a light theme instead.

Just by turning the table and introduce a dark theme first, we can save a massive amount of electricity. If you came to this article with the question: Does dark mode save power? Then the answer is “Yes, as long as your device has an OLED display, then it will save power”.