howtosimply.com/guides/samsung-galaxy-screen-brightness-keeps-changing-5-causes/ · Checked October 2026 · Samsung Galaxy A57 (One UI 9, Android 17 (build A576BXXU6BZIE)) and Samsung Galaxy A57 5G (One UI 8.5, Android 16)

In this guide

Open Display
Switch off Adaptive brightness
Set the level yourself
Check Power saving
Let a hot phone cool down
If you do not see this option
If this does not work
Good to know
Video demo
Sources

Quick answer

Adaptive brightness changes the screen with the light around you; turn it off under Settings, Display. Power saving, a hot phone and a nearly empty battery also dim the screen. Eye comfort shield changes the colour, not the brightness.

4 of 5 steps with real screenshots · 2 official sources below

Device: Android
Shown on: Samsung Galaxy A57 (SM-A576B), One UI 9, Android 17 (build A576BXXU6BZIE), Samsung Galaxy A57 5G (SM-A576B), One UI 8.5, Android 16
App: Settings
Real screenshots: 4 of 5 steps
What we did: Observed: looked at each screen, changed nothing
Our phone: Shown on Galaxy A57, One UI 8.5
Checked: October 2026
Sources: 2 official, linked below

Step by step

Open Display
Open Settings and tap Display.
Watch these steps Done
Switch off Adaptive brightness
It was on on our phone. Off, the brightness stays where you set the slider above it. It can also be switched from the quick panel.
Done
Set the level yourself
Drag the Brightness slider. Samsung notes a prompt to turn Adaptive brightness back on may appear once after a restart if you set it above 90%.
Done
Check Power saving
Settings, Battery, Power saving lowers brightness to save battery.
Done
Let a hot phone cool down
The phone dims itself when it overheats, for example in the sun, while charging or gaming, or when the battery is critically low. This is protection, not a fault.
Done

Watch these steps

The video loads from YouTube when you press play.

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If you do not see this option

Adaptive brightness is not where you expect Samsung says you can also swipe down, touch and hold the Brightness slider in the quick panel and turn Adaptive brightness off there. Source: What to do if the screen brightness changes automatically on your Samsung Galaxy device
The Power saving settings are greyed out Samsung says you can only change the Power saving settings while Power saving is off. Source: Stop the screen brightness from dimming on your Galaxy phone or tablet

If this does not work

The screen dims or goes dark by itself Samsung says a case or screen cover over the proximity sensor near the top of the screen can dim or turn off the screen. Clean the sensor with a dry microfibre cloth. Source: Stop the screen brightness from dimming on your Galaxy phone or tablet
It dims when the battery is low Samsung says brightness may drop to stretch the battery when the level is very low. Charge the phone. Source: What to do if the screen brightness changes automatically on your Samsung Galaxy device

About this guide

Samsung says the brightness follows the surrounding light, the phone's temperature and the battery level. Only the first is a setting you can switch off.

Good to know

Eye comfort shield makes the screen warmer and yellower, which can look darker. It was off on ours: how to turn on Eye comfort shield on a Samsung Galaxy phone.

Even darker than the lowest setting? How to use Extra dim on a Samsung Galaxy phone.

In short: Display, Adaptive brightness off, set the slider. Power saving, heat and a low battery also dim the screen.

Sources

Links checked in October 2026. Menus and features can change after software updates. These steps match the version named at the top.