Normal direction

Blue front · Red back

Drop model + deps OBJ / MTL / GLB / GLTF / BIN / textures

Blue is front; red is back.

Initializing normal checker…

Check result

Normal stats

About 3D Normal Direction Check

This checker overrides every triangle with a "front blue · back red" shader, then compares face normals to averaged vertex normals to detect suspected reversal (dot < -0.35). Reports include reversal count, reversal ratio, degenerate triangles and missing-normal triangles. Useful for fixing imported black-face / single-sided / flipped-normal issues before marketplace listing, AR / WebGL embedding.

Related tools

Asset Package QAWhole-pack QA includes normal checks.
Model PreviewSee the original material.
UV InspectorUV and normals often fail together.
OBJ ↔ GLB ConverterAuto-recompute missing normals.
PBR Material CheckNormal map OpenGL / DX bias.