Resolved Why do people keep saying Dark Mode reduces battery consumption?

[Iwavvns]

I own the following Apple products, with dates of purchase:
Apple iPhone 13 - purchased November 5, 2023 (Battery capacity 99%)
Apple iPhone 15 - purchased July 7, 2024 (Battery capacity 100%)
Apple iPad 10th gen - purchased November 3, 2024 (Battery capacity 100%)

I only allow supervised charging of my devices; begin charging at 20% and remove from charger at 80%.

I kept my iPhones on Dark Mode until this month because I kept seeing so many people saying Dark Mode saves battery life. When I got my iPad 10th gen last week I decided to run a test of the battery life in Dark Mode vs. Light Mode. What I found was that Dark Mode on my iPhones doesn't save any battery life at all, both phones require charging every two days regardless of Dark/Light Mode settings. At this rate my iPhone batteries should last around 5 years.. even in Light Mode.

I don't stream music or video, but I do listen to Podcasts in the Apple Podcast app all day on my iPhones, which doesn't seem to use much battery power at all. My iPad 10th gen is used for office/document work and web browsing, and this iPad seems to be falling into the same recharging habits as my iPhones; charging once every two days. Fine with me, I never did like Dark Mode anyway.. it's downright ugly and Apple Maps is difficult to read outdoors.

So, does Dark Mode only help with battery life for people who have their iPhone screens active for more than two hours per day?

 

[waw74]

it depends on the display technology.

LCDs use a backlight that is always on. There's an LCD screen in front of that that will block light for the dark parts of the image, and let light though for the light parts.

OLEDs like on the iPhone individually light up each pixel. So black part of the image, that individual pixel is not lit up. White part of the image, that pixel is on. they draw more power the brighter the image. and the more parts of the screen are lit up.

If you've got a display that lights up each pixel, dark mode lights up less pixels, using less power.
If you've got a display that has an always on backlight, the backlight is drawing power whenever the screen is on.

In reality it probably doesn't reduce power that much, also depends on the background of the screen. in a reader app, probably saves you a bit, as you change from 75% lit to 25% lit. For videos, maybe not so much

 

[BuggyGT]

Dark mode does use less battery but perhaps maybe not in with your usage case. This video is old but he is using a robot that navigates the screen and both phones are doing the same exact tasks so it is apples to apples comparison with the only difference being light and dark mode. 2nd video not as in depth but you get the general idea.

EDIT: this is for the OLED screens

 

[FreakinEurekan]

I'm sure there's a measurable difference in power draw between dark mode and light mode.

That doesn't mean it's a NOTICEABLE difference - and it's certainly not a criteria I'd use in deciding whether or not to use Dark Mode. It's just a statistic.

 

[Iwavvns]

Dark mode does use less battery but perhaps maybe not in with your usage case. This video is old but he is using a robot that navigates the screen and both phones are doing the same exact tasks so it is apples to apples comparison with the only difference being light and dark mode. 2nd video not as in depth but you get the general idea.

EDIT: this is for the OLED screens

Yeah, my iPhones have OLED displays but the iPad has an LCD display. I'm thinking this battery savings depends entirely on individual usage cases where the screen is in use. I mean, if the display is off (Podcasts App, Music), then there won't be any battery savings due to Dark Mode.

I will definitely force myself to get used to Dark Mode if I decide to stream videos.

 

[Jackbequickly]

It would make sense that OLED screen would use less power in dark mode. I prefer it, not to save power, but I find it easier on my eyes.

 

[Shirasaki]

Yes people do say dark mode saves battery, but my M1 iPad doesn’t have OLED and I like to use the iPhone the way I feel like it, not catering to maintaining high battery health percentage after 2-3 years.
Even if there is a noticeable power saving difference, I don’t think it’s really that big of a deal to matter to me and many others.

 

[ProbablyDylan]

Normal people don't use their devices with enough screen on time for it to be a noticeable difference. Use your phone / tablet / whatever in the mode that's most comfortable for your eyes.

 

[UKapple73]

Only OLED screens will save battery life in dark mode - won’t make any difference to LCD ones

 

[Reverend Benny]

Only OLED screens will save battery life in dark mode - won’t make any difference to LCD ones

I guess it depends on the LCD tech being used. In theory mini-led ones would save battery since the mini-leds in the dark area wouldn't be active.
Not sure how much difference it would make in a real life scenario tho.

 

[UKapple73]

I guess it depends on the LCD tech being used. In theory mini-led ones would save battery since the mini-leds in the dark area wouldn't be active.
Not sure how much difference it would make in a real life scenario tho.

Correct, mini led would save in dark mode, like say a MacBook Pro, but in a phone scenario mini led is impossible as the leds are too large, they would need to be micro leds and that’s the next step I guess