Material Merger

Material Merger is an Editor tool that reduces the number of materials used in your project. It streamlines your assets by matching duplicates and similar materials and automatically swapping out redundant materials in your project's game objects and prefabs, with the option to delete redundant materials.
This will make your project easier to manage, with up to hundreds fewer unnecessary assets in material folders. You can even match similar materials with full control over how specific the matching must be across properties such as R, G, B, Alpha or Specular properties.
'Project bloat' can be caused by importing 3D models into Unity without cleaning them up and checking their materials to ensure they're not already in existence (creating duplicates). On a medium-sized project, materials can number in the thousands and up to 50% of those materials could be copies of each other or so similar that you can't tell the difference with the naked eye.
Material Merger supports Unity 5 Standard Shaders and materials based on the following legacy shaders:
Diffuse
Bumped Diffuse
Transparent Diffuse
Transparent Bumped Diffuse
Specular
Bumped Specular
Transparent Specular
Unlit Transparent
VertexLit
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