SRP Batcher
Cheaper draw calls in URP and HDRP
Also known as: Scriptable Render Pipeline Batcher · SRP Batcher compatible · SRP batching
Definition
The SRP Batcher is a rendering feature of Unity's Scriptable Render Pipelines (URP and HDRP) that cuts the CPU cost of draw calls. It keeps material data in GPU memory and draws objects that use the same shader variant one after another without resetting state for each material. It does not reduce the number of draw calls, but it makes each one cheaper, so scenes with many materials render faster.
In production
It is on by default in URP and HDRP, and a shader must be compatible with it; Shader Graph shaders and the URP Lit shaders are, and the shader inspector shows the status. Custom shaders that do not declare their properties in a constant buffer, and objects that use MaterialPropertyBlock, fall back to slower paths. Prefer many materials that share a shader over a few shaders with many variants.
