Check how many shader variants you have

You can use logging and profiling tools to check how many shader variants Unity compiles, and identify ways you can remove (strip) variants to improve build times and reduce memory usage. You can do the following:

• Get a list of shader variants the Editor uses
• Get a list of shader variants Unity creates at build time
• Get a list of shader variants Unity compiles at runtime
• Check how much memory shaders use at runtime
• Highlight missing shaders at runtime

Get a list of shader variants Unity creates at build time

After you build your project, open the Editor.log log file and search for Compiling shader to see which variants Unity compiles and strips. For the location of Editor.log, refer to log files.

For example:

Compiling shader "Sprites/Default" pass "" (vp)
    Full variant space:         8
    After settings filtering:   8
    After built-in stripping:   4
    After scriptable stripping: 4
    Processed in 0.00 seconds
    starting compilation...
    finished in 0.03 seconds. Local cache hits 0 (0.00s CPU time), remote cache hits 0 (0.00s CPU time), compiled 4 variants (0.09s CPU time), skipped 0 variants
    Prepared data for serialisation in 0.00s

If you use the Universal Render Pipeline (URP) or the High Definition Render Pipeline (HDRP), refer to the following:

• Reducing shader variants in URP
• Reduce shader variants in HDRP

Get a list of shader variants Unity compiles at runtime

To get a list of shader variants Unity compiles at runtime, use either of the following approaches:

• Record which pipeline state objects (PSOs) your application uses with the GraphicsStateCollection API. For more information, refer to Trace and manage PSO data collections.
• Track which shader variants Unity uploads to the GPU each frame. For more information, refer to the VariantsUploadedToGpuLastFrame API.

You can also log compiled shader variants in the Console window and in a log file. Follow these steps:

1. Go to Edit > Project Settings > Graphics.
2. Under Shader Loading, enable Log Shader Compilation.
3. When you build your project, enable Development Build in the build settings.
4. In the Console WindowA Unity Editor window that shows errors, warnings and other messages generated by Unity, or your own scripts. More info
   See in Glossary, select Editor and enable Full Log [Developer Mode Only].
5. Start the application you built.

Unity prints a Compiled shader message in the Console Window when it compiles a shader for the GPU.

Check how much memory shaders use at runtime

Use the Memory Profiler module or the Memory Profiler package to check how much memory shaders are using at runtime. If a shader uses a lot of memory, you can experiment with stripping its variants.

Highlight missing shaders at runtime

In Unity 2022.3 and above, you can force Unity to show a pink error shader during runtime, when a Material tries to use a missing shader variant.

1. Go to Edit > Project Settings > Player.
2. Under Other Settings, in the Shader Settings section, select Strict shader variant matching.

You can also enable this in C# scripts using strictShaderVariantMatching.

When you do this, Unity shows a warning in the console with the missing variant and its keywords. You can use this during stripping to check you don’t remove shader variants your project needs.