Choose a method for optimizing draw calls

Use draw call optimization if the CPU sends too many draw calls to the GPU, which is also known as being CPU-bound. For more information about draw calls, refer to Introduction to optimizing draw calls.

Check the number of draw calls

To check if your sceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary sends too many draw calls, do any of the following:

• Open the Rendering Statistics window and check the SetPass calls value.
• Open the ProfilerA window that helps you to optimize your game. It shows how much time is spent in the various areas of your game. For example, it can report the percentage of time spent rendering, animating, or in your game logic. More info
  See in Glossary and select the Rendering section to display the number of draw calls.
• Check the number of draw calls in the Frame Debugger.

Choose optimization methods

The supported and recommended methods for optimizing draw calls depend on whether you use the Universal Render PipelineA series of operations that take the contents of a Scene, and displays them on a screen. Unity lets you choose from pre-built render pipelines, or write your own. More info
See in Glossary (URP), the High Definition Render Pipeline (HDRP), or the Built-In Render Pipeline (BIRP).

If you have many instances or lights, you can also use optimize mesh rendering using level of detail (LOD).

To get the best results from any draw call optimization method, do the following:

• Use the same materials for different GameObjectsThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
  See in Glossary as much as possible.
• If you want to render the same meshThe main graphics primitive of Unity. Meshes make up a large part of your 3D worlds. Unity supports triangulated or Quadrangulated polygon meshes. Nurbs, Nurms, Subdiv surfaces must be converted to polygons. More info
  See in Glossary with different properties, for example different colors, use Material Variants instead of multiple materials.
• Avoid using the MaterialPropertyBlock API in URP and HDRP.

Use multiple optimization methods

You can use multiple draw call optimization methods in the same scene, but each GameObject uses only one of the following methods, in this priority order:

1. SRP Batcher, and static batching if you enable it.
2. GPU instancing, including the GPU Resident Drawer or the BatchRendererGroup API.
3. Dynamic batching.

Additional resources

• Shader variantsA verion of a shader program that Unity generates according to a specific combination of shader keywords and their status. A Shader object can contain multiple shader variants. More info
  See in Glossary
• Fantasy Kingdom in Unity 6, which uses the GPU Resident Drawer.
• SRP Batcher: Speed up your rendering
• BatchRendererGroup sample: Achieve high frame rate even on budget devices
• Megacity Metro, which uses the BatchRendererGroup API to render a large number of objects.