Why Does My iPhone 15 Brightness Keep Changing? Tips to Fix It

To fix the issue of your iPhone 15 brightness changing automatically, you’ll need to adjust the Auto-Brightness and True Tone settings. This overview will guide you through the steps to manage these features and maintain consistent screen brightness.

After completing the action, your iPhone 15 should maintain a consistent brightness level based on your preferences, providing a more comfortable and personalized user experience.


Have you ever noticed your iPhone 15 screen brightness fluctuating without you touching any settings? It’s like your phone has a mind of its own, right? Well, there’s no need to worry, it’s not haunted. Your iPhone is equipped with features designed to automatically adjust the brightness for optimal viewing experience. But why is this important?

For starters, it can help save battery life and reduce eye strain by adapting to the surrounding lighting conditions. This is crucial for those of us who use our phones throughout the day and in various environments. Plus, let’s face it, no one likes squinting at their screen on a sunny day or being blinded by a too-bright screen in a dark room. This topic is relevant to any iPhone 15 user who wants to understand their device better and control its settings for a more enjoyable viewing experience.

Step by Step Tutorial: Adjusting iPhone 15 Brightness Settings

Before we dive into the steps, let’s clarify what we’re aiming for. By adjusting the brightness settings on your iPhone 15, you’ll be able to have a consistent screen brightness that doesn’t change unexpectedly.

Step 1: Open the Settings app

Open the Settings app on your iPhone 15.

This is where all the magic happens. The Settings app is the gateway to customizing your iPhone to fit your needs.

Step 2: Navigate to Accessibility

Scroll down and tap on Accessibility.

Accessibility settings cover a range of options designed to make your iPhone easier to use.

Step 3: Tap on Display & Text Size

In the Accessibility menu, find and tap on Display & Text Size.

This section controls features that affect how content appears on your screen.

Step 4: Toggle off Auto-Brightness

Scroll to the bottom and toggle off the Auto-Brightness option.

By turning off Auto-Brightness, your iPhone will no longer automatically adjust its screen brightness based on surrounding lighting conditions.

Step 5: Return to Settings and tap on Display & Brightness

Go back to the main Settings menu and select Display & Brightness.

This is another hub for adjusting how your screen looks.

Step 6: Toggle off True Tone

Toggle off the True Tone option.

True Tone adjusts the white balance of your display to match the ambient light, which can also cause changes in brightness.


Consistent brightnessTurning off Auto-Brightness and True Tone maintains a consistent level of brightness, which can be more comfortable for your eyes.
Battery savingsManually managing your brightness can lead to better battery life, as you can set it to the lowest comfortable level.
Personal preferenceYou have complete control over your screen brightness, allowing you to adjust it according to your personal preference.


Manual adjustmentsWithout Auto-Brightness, you may need to manually adjust your screen brightness more frequently, which can be inconvenient.
Less adaptive to environmentsYour screen won’t automatically adapt to different lighting conditions, potentially affecting visibility.
Potential eye strainA consistent brightness level may not always be ideal for every situation, possibly leading to eye strain.

Additional Information

While adjusting your iPhone 15 brightness settings can help maintain a consistent screen level, there are other factors to consider. For instance, the Night Shift feature, which adjusts screen colors to warmer tones in the evening, can also affect perceived brightness. Additionally, certain apps may override your brightness settings, particularly those used for reading or video playback.

It’s also important to note that while battery life can be preserved by manually setting your brightness, Auto-Brightness is designed to be energy-efficient. So if you’re not bothered by the changing screen brightness, it might be worth keeping it on for the potential battery savings.

Remember, your iPhone 15 brightness settings are there to make your experience as comfortable as possible, so feel free to experiment with what works best for you.


  1. Open the Settings app.
  2. Navigate to Accessibility.
  3. Tap on Display & Text Size.
  4. Toggle off Auto-Brightness.
  5. Return to Settings and tap on Display & Brightness.
  6. Toggle off True Tone.

Frequently Asked Questions

Why does my iPhone 15 brightness keep changing?

Your iPhone 15 brightness changes automatically due to the Auto-Brightness and True Tone features, which adjust the screen based on ambient lighting conditions.

Will turning off Auto-Brightness affect my battery life?

Turning off Auto-Brightness may affect your battery life as you might manually set the brightness higher than what the automatic setting would use.

Can apps override my brightness settings?

Yes, some apps, particularly those for reading or video playback, may override your manual brightness settings.

What is True Tone, and why does it affect brightness?

True Tone adjusts the white balance of your display to match the ambient light, which can make the screen appear brighter or dimmer depending on the environment.

Is it better to have Auto-Brightness on or off?

It depends on personal preference. Auto-Brightness can save battery and adapt your screen to environmental conditions, while turning it off gives you full control over the brightness level.


Ah, the joys of technology—so convenient yet sometimes puzzling, like when your iPhone 15 brightness decides to change on its own. But now, armed with the knowledge of Auto-Brightness and True Tone, you can take control of your screen’s luminosity. Whether you prefer the set-it-and-forget-it approach or want to manually adjust to your heart’s content, your iPhone 15 is flexible enough to accommodate your preferences.

Remember, at the end of the day, your comfort and convenience are what matter most. So go forth, tweak those settings, and enjoy your personalized, consistently bright iPhone experience.

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