Description
On Android, system font scaling values between 1.0 to 1.5 aren't applied properly on certain font sizes. Please see the screenshots below.
Steps to reproduce
Android
- Install the app
- Use
adb shell settings put system font_scale x.x to set font scaling value or change it through setting
- Make sure to restart the app after changing the value
iOS
- Install the app
- Use simulator settings or the settings app to change the font scaling value
- Make sure to restart the app after changing the value
React Native Version
0.85.3
Affected Platforms
Runtime - Android
Output of npx @react-native-community/cli info
info Fetching system and libraries information...
System:
OS: macOS 15.7.7
CPU: (12) arm64 Apple M4 Pro
Memory: 559.30 MB / 48.00 GB
Shell:
version: 0.109.1
path: /Users/burakguner/.cargo/bin/nu
Binaries:
Node:
version: 24.13.0
path: /Users/burakguner/.nix-profile/bin/node
Yarn:
version: 1.22.22
path: /Users/burakguner/.nix-profile/bin/yarn
npm:
version: 11.6.2
path: /Users/burakguner/.nix-profile/bin/npm
Watchman:
version: 2026.01.19.00
path: /Users/burakguner/.nix-profile/bin/watchman
Managers:
CocoaPods:
version: 1.16.2
path: /Users/burakguner/.local/share/gem/ruby/3.3.0/bin/pod
SDKs:
iOS SDK:
Platforms:
- DriverKit 25.2
- iOS 26.2
- macOS 26.2
- tvOS 26.2
- visionOS 26.2
- watchOS 26.2
Android SDK:
API Levels:
- "30"
- "31"
- "34"
- "35"
- "36"
Build Tools:
- 35.0.0
- 36.0.0
- 36.1.0
System Images:
- android-30 | ARM 64 v8a
- android-34 | Google Play ARM 64 v8a
- android-35 | Google APIs ARM 64 v8a
- android-35 | Google Play ARM 64 v8a
- android-36.1 | Google Play ARM 64 v8a
Android NDK: Not Found
IDEs:
Android Studio: 2025.3 AI-253.32098.37.2534.15336583
Xcode:
version: 26.2/17C52
path: /usr/bin/xcodebuild
Languages:
Java:
version: 21.0.8
path: /Users/burakguner/.nix-profile/bin/javac
Ruby:
version: 3.4.8
path: /Users/burakguner/.nix-profile/bin/ruby
npmPackages:
"@react-native-community/cli":
installed: 20.1.0
wanted: 20.1.0
react:
installed: 19.2.3
wanted: 19.2.3
react-native:
installed: 0.85.3
wanted: 0.85.3
react-native-macos: Not Found
npmGlobalPackages:
"*react-native*": Not Found
Android:
hermesEnabled: true
newArchEnabled: true
iOS:
hermesEnabled: true
newArchEnabled: true
Stacktrace or Logs
MANDATORY Reproducer
https://github.com/atlj/reproducer-android-broken-font-scaling
Screenshots and Videos
Android
All of these screenshots were taken with an Android 16 emulator. However the issue is reproducible on Android 13, Android 14 and Android 15 as well.
What to look for
In the following screenshots, notice how text with font size 30 isn't scaled properly between font scale 1 to 1.5 (except 1.01 which might be useful to spot the exact bug)
| 1 |
1.01 |
1.1 |
1.2 |
1.3 |
1.5 |
1.6 |
2 |
 |
 |
 |
 |
 |
 |
 |
 |
A non React Native App
Here is how the settings app behaves
iOS
iOS applies font scaling properly
Description
On Android, system font scaling values between 1.0 to 1.5 aren't applied properly on certain font sizes. Please see the screenshots below.
Steps to reproduce
Android
adb shell settings put system font_scale x.xto set font scaling value or change it through settingiOS
React Native Version
0.85.3
Affected Platforms
Runtime - Android
Output of
npx @react-native-community/cli infoStacktrace or Logs
MANDATORY Reproducer
https://github.com/atlj/reproducer-android-broken-font-scaling
Screenshots and Videos
Android
All of these screenshots were taken with an Android 16 emulator. However the issue is reproducible on Android 13, Android 14 and Android 15 as well.
What to look for
In the following screenshots, notice how text with font size 30 isn't scaled properly between font scale 1 to 1.5 (except 1.01 which might be useful to spot the exact bug)
A non React Native App
Here is how the settings app behaves
iOS
iOS applies font scaling properly