I was told that using dark mode on my laptop and smartphone will save battery life; is this true?
This question was answered on March 5, 2020. Much of the information contained herein may have changed since posting.
With all of the time we spend staring at digital displays throughout the day, it’s likely that you’re experiencing eye strain, blurred vision, dry eyes and maybe even headaches.
Dark mode is an option that can help reduce some of these symptoms by reducing the amount of bright light you are staring at all day.
As for battery life, the answer depends greatly on what type of display your device is using.
What is Dark Mode?
Dark mode switches the colors of your display so that items that are normally light in color - like the background - become dark and dark items - like text - become light in color.
It’s not hard to understand how this can be especially helpful when you are viewing the display in low light situations. If you use Google Maps when you’re driving, you’ve likely experienced the app automatically switching to a dark mode when it gets dark outside.
Changing the setting varies greatly based on your OS and apps, but looking through the 'Settings' menu for 'Dark Mode' is generally how to turn it on.
Does It Save Battery Power?
It stands to reason that using less light should use less power, but that’s not how displays work in many of our devices.
The hype around the battery savings associated with dark mode was likely elevated by a Google VP last year during the Google I/O event.
What the Google executive was referring to when he proclaimed the power savings of dark mode was on devices that have an OLED display. OLED displays turn each pixel on and off, so pixels that are black draw no power. Using more black pixels on OLED displays can have a measurable impact on power usage.
If your device uses an LCD display, it uses backlighting, which is quite different from a power consumption standpoint.
As long as the display is turned on with LCDs, the same amount of light is being generated whether the screen is white or black. The color black on LCD displays is generated by placing a filter over the backlighting, so the power consumption is essentially the same.
This is why the best way to reduce LCD power usage is to reduce the brightness, because it controls how bright the backlight shines.
Which Screen Do I Have?
If you have a newer smartphone from Apple or Samsung or any of the Google Pixel phones, you’ll likely have an OLED display. Apple introduced OLED starting with the iPhone X and newer models with the exception of the standard iPhone 11.
OLED displays in laptops started becoming more common in 2019, so if you have an older laptop, it’s most likely using a backlit LCD.
The easiest way to know is to do an internet search for each of your devices followed by the words ‘display type’.
Harder to Read?
As great as dark mode may work for some people, it can be harder to read for those that have any of the varying degrees of astigmatism, whether you’ve been diagnosed with it or not.
The only way to know is to try it for yourself!
About the author
Ken Colburn of Data Doctors on March 5, 2020