File Format Reference

Low-level documentation of the SketchUp .skp binary format established from observed file behavior and interoperability testing by the skppy project.

Document

Description

SKP Format

ZIP/VFF format emitted for SketchUp 2021+ - TLV encoding, all root tags, entity structure

Legacy Format

Overview of the pre-ZIP object graph emitted through SketchUp 2020

Legacy Container

Header, strings, version map, references, and root order

Legacy Class Catalog

Tabular class mappings and schema matrices

Legacy Field Layouts

Confirmed version-gated fields by feature family

UV Projection

Texture projection matrix math and TLV path

Edge Shading Flags

Soft/smooth edge flags and importer shading behavior

Tag Map

Machine-readable YAML - 422 mapped tags with payload type annotations

Findings are observation-based and may evolve as broader samples are tested. This documentation is not affiliated with or endorsed by Trimble Inc.