Font weight issue on React Native 0.83 when using custom font

[jaredrkozar]

Description

I'm currently working on an app that's using a custom font, and am noticing a weird issue that has to do with font weight. Note that this issue only occurs on iOS; it looks fine when running on Android.

On React Native 0.82.1, when rendering a Text component with the style

sampleText: { fontFamily: [custom font, regular font weight], fontWeight: '200', fontSize: 30 },

our text looked good. (It's the first screenshot posted below)

However, on React Native 0.83, when rendering text with the exact same style, I noticed that the font weight was much thicker than I expected it to be. (See the second screenshot). I noticed that if I removed "fontWeight: 200" from the associated style, then it looked better, and it rendered as I expected it to.

Is this an intentional change?

This reddit post might be related to this issue

Steps to reproduce

1. Create a Text component
2. In its associated style in the stylesheet, add custom font and set a font weight
3. if you’re running on React Native 0.83, the font weight should be thicker than expected

React Native Version

0.83.0

Affected Platforms

Runtime - iOS

Output of npx @react-native-community/cli info

info Fetching system and libraries information...
System:
  OS: macOS 26.1
  CPU: (12) arm64 Apple M2 Max
  Memory: 130.11 MB / 32.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 22.20.0
    path: /Users/jkozar/.nvm/versions/node/v22.20.0/bin/node
  Yarn:
    version: 4.6.0
    path: /Users/jkozar/.nvm/versions/node/v22.20.0/bin/yarn
  npm:
    version: 10.9.3
    path: /Users/jkozar/.nvm/versions/node/v22.20.0/bin/npm
  Watchman: Not Found
Managers:
  CocoaPods:
    version: 1.16.2
    path: /opt/homebrew/bin/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 25.1
      - iOS 26.1
      - macOS 26.1
      - tvOS 26.1
      - visionOS 26.1
      - watchOS 26.1
  Android SDK: Not Found
IDEs:
  Android Studio: 2025.1 AI-251.26094.121.2512.13840223
  Xcode:
    version: 26.1/17B55
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.8
    path: /usr/bin/javac
  Ruby:
    version: 2.6.10
    path: /usr/bin/ruby
npmPackages:
  "@react-native-community/cli":
    installed: 20.0.0
    wanted: 20.0.0
  react:
    installed: 19.2.0
    wanted: 19.2.0
  react-native:
    installed: 0.83.0
    wanted: patch:react-native@npm%3A0.83.0#~/.yarn/patches/react-native-npm-0.83.0-577d0f2d83.patch
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: true
iOS:
  hermesEnabled: true
  newArchEnabled: true

Stacktrace or Logs

This isn’t a crash - it’s an issue with a custom font.

MANDATORY Reproducer

None

Screenshots and Videos

Here’s what this issue looks like on React Native 0.82.1

Here’s what it looks like on React Native 0.83

[react-native-bot]

[!WARNING] Missing reproducer: We could not detect a reproducible example in your issue report. Reproducers are mandatory and we can accept only one of those as a valid reproducer:

• For majority of bugs: send us a Pull Request with the RNTesterPlayground.js edited to reproduce your bug.
• If your bug is UI related: a Snack
• If your bug is build/upgrade related: a project using our Reproducer Template

You can read more about about it on our website: How to report a bug.

[ertucaglar]

I have same issue +1

[mustafaabobakr]

same issue

[SameedSharif-cmyk]

Facing similar issue.

[jaredrkozar]

Thank you for making a PR to fix this bug @ptptsw

[uday-zluck]

Facing same issue

[uday-zluck]

Issue (RN 0.83, iOS)

When using custom fonts on iOS, setting both fontFamily and fontWeight can make text look overly bold.

{
  fontFamily: 'YourFont-Regular',
  fontWeight: '600',
}

Why this happens iOS applies fontWeight on top of the font file’s built-in weight, so the weight ends up being applied twice.

Recommended fix ✅ Use the specific PostScript font name and don’t set fontWeight on iOS.

{
  fontFamily: 'Montserrat-SemiBold',
}

Alternative If you want to keep the same style object, only apply fontWeight on Android.

{
  fontFamily: 'YourFont-Regular',
  ...(Platform.OS === 'android' ? { fontWeight: '600' } : {}),
}

Notes PostScript font names already include the correct weight. iOS loads that exact font file, so removing fontWeight prevents the extra weight transformation.