Unused packages

Unused Unity packages can add several megabytes to a WebGL build even when the game does not use them.

What to check first

Remove the New Input System if your game uses only the old Input Manager. This package alone adds around 2.4 MB.
Delete packages that were added by default but not used:
- Visual Scripting
- XR / AR modules
- Analytics / Ads packages if not integrated
If you use Cinemachine only for simple cameras, consider removing it and using a lighter setup.
Clean Quality and Graphics settings. Built-in features such as shadows can pull extra shaders into the build.

How to do

Example

The example below uses an empty Unity project to show how each setting affects final WebGL build size.

Step 1: Create an Empty Unity project for WebGL (we will use Unity 6000.0.23f1 + Built-In Render Pipeline)

Step 2: Switch platform to WebGL and make a build to check the default size

The initial build is around 9.7 MB, which is too large for a minimal WebGL project.

Step 3: First thing to do! Go to build settings and change “Code Optimization: Build Size with LTO”

The build size is now 9 MB.

Step 4: Go to Player Settings → set Compression: Brotli and enable Name files as hashes

The build is now 6.8 MB, reduced from 9.7 MB. Continue with the next settings.

Step 5: Now let’s change IL2CPP Code Generation to “Smaller Builds” and change C++ Compiler Configuration to Master

Step 6: Choose texture compression (ASTC / DXT / ETC2). Enable Crunch for textures when possible

Step 7: Set Color Space: Gamma if the game supports it (≈100 KB saving)

Step 8: Set Managed Stripping Level: High. Test the game after enabling stripping because it may remove required code.

Also enable texture mipmap stripping

Step 9: Remove unused features and packages

New Input System adds ~2.4 MB. If the project does not use it, remove the package to reduce the build to ~2.2 MB.

After these changes, the build is reduced from about 10 MB to about 2.2 MB.

Last updated 1 month ago