Texturing & materials · Beginner

BSDF (shader)

The rule a renderer uses for how light bounces off or passes through a surface

Also called Principled BSDF, Bidirectional scattering distribution function

What is a BSDF?

A BSDF (bidirectional scattering distribution function) is the math a renderer uses to decide how light bounces off, or passes through, a surface. In Blender, the Principled BSDF is the all-in-one PBR surface shader: one node with base color, metallic, roughness and more, covering most real materials.

Think of it like this

Like a recipe card for a surface: tell it how shiny, how metallic and what color, and it tells the renderer how light behaves when it lands there.

Where it fits in a 3D project

  1. Create
  2. Surface
  3. Rig
  4. Animate
  5. Render
  6. Export

Surface: Giving the shape its color and material: UVs, textures and shaders.

How a BSDF works

  1. 01Light arrives at a point on a surface from some direction.
  2. 02The BSDF works out how much bounces off, scatters inside or passes through, and where it goes.
  3. 03In Blender, the Principled BSDF sets this through inputs like Base Color, Roughness and Metallic.
  4. 04Its output connects to the Surface socket of the Material Output node.

BSDF (shader) vs material

PropertyBSDF (shader)Material
What it isOne shader node describing light responseThe whole surface setup on an object
ContainsInputs like color, roughness, metallicBSDFs, textures and other nodes
In BlenderA node in the Shader EditorAn entry in Material Properties
How manyOften one per material, sometimes mixedOne per material slot

Think of the material as the container and the BSDF as the engine inside it; most beginner materials are one Principled BSDF with textures plugged in.

Where a BSDF is used

  • Building plastic, metal, wood, glass and skin from one node
  • Plugging in the maps from a PBR texture set
  • Matching materials between Blender and other PBR tools

Beginner tip

Change one input at a time on the Principled BSDF and watch the preview. Roughness and Metallic do most of the work; leave the advanced sections alone until the basics look right.

Terms related to a BSDF

BSDF (shader) FAQ

What does BSDF stand for?
Bidirectional scattering distribution function. In plain terms, it is a rule for how light that hits a surface from one direction leaves it in every other direction, covering both reflection and light passing through.
What is Principled BSDF in Blender?
Blender’s default surface shader, added to every new material. It combines diffuse, metal, gloss, glass, subsurface scattering, coat, sheen and emission in one node that follows PBR rules, so it can make most real-world materials. It works in both of Blender’s built-in render engines.
What are the main Principled BSDF settings?
Base Color sets the color, Metallic switches between non-metal and metal, and Roughness goes from mirror-sharp to matte. Normal takes a normal map for fine detail, Alpha controls see-through areas, and Transmission makes glass and liquids.
Is a BSDF the same as a shader?
A BSDF is one kind of shader: the kind that describes how a surface reflects and transmits light. Other shaders in Blender handle emission, volumes and holdouts, and a material can mix them with BSDFs.

Updated October 29, 2026 · Browse all 3D terms