Autodesk
Exporting STEP from Inventor and checking your BOM.
Inventor puts the assembly and all parts in one STEP file, including materials. Below: the export, the BOM to Excel and how to check them against each other.
Published 20 September 2026
01 Export
Exporting STEP from Autodesk Inventor.
- 1 Open the assembly and choose File > Export > CAD Format.
- 2 Choose STEP (*.stp, *.step) as file type and click Options.
- 3 Choose Application Protocol 214 (Automotive Design). AP242 is not available for assemblies in Inventor.
- 4 Leave Spline Fit Accuracy at its default, unless you have a reason to change it.
- 5 Save and check the export in the free STEP viewer.
Everything in one file
For an assembly, Inventor saves the assembly and all referenced parts in one STEP file. So there is nothing to merge.
Colours become RGB
Inventor appearances are converted to RGB colours on the STEP solids. Material names do stay in the file as a property.
Watch out for default materials
In Inventor exports we often see materials such as "Generic" or "Steel, Mild". That usually means no material has been assigned. In the free check those parts are listed together.
02 BOM
BOM from Autodesk Inventor to Excel.
- 1 Open the assembly, and on the Assemble tab in the Manage panel click Bill of Materials.
- 2 In the window click Export Bill of Materials.
- 3 Choose the view you need (for example Structured) and which data to include.
- 4 Enter a file name and type and save as a spreadsheet.
Microsoft Excel must be installed on your computer to export to a spreadsheet.
No BOM at hand? The free STEP to Excel makes one from the model itself: per part the total quantity, the material and the dimensions.
03 Check
Does the model match the BOM?
Export the STEP and the BOM at the same moment: otherwise you compare two versions. Then you can lay them against each other.
Inventor puts material and density per part in the STEP. That lets a check also see whether similar parts suddenly have a different material.
Free, in your browser
- Parts or subassemblies lying double in the same place
- Parts that touch nothing, with the distance in mm
- Parts without material or with a default value such as Generic
- The same shape under different names
With BOMproof
Your drawing and your BOM as well.
BOMproof lays the STEP from Autodesk Inventor next to your PDF drawings and your Excel BOM: quantities per position, title block and revisions, materials on the drawing against the model. Every comment gets a pin in 3D and a balloon on the drawing.
Sources
04 Frequently asked questions
Inventor and STEP.
01 Why can I not choose AP242 for my assembly?
In Inventor, AP242 is only available for single parts, not for assemblies. For an assembly choose AP214; it contains the full product structure with quantities.
02 My BOM does not match the model. How do I find out why?
Export the STEP and the BOM at the same moment and have them laid side by side. The free check already shows whether parts lie double in the model; BOMproof compares the Excel BOM line by line with the model.
03 Which STEP version is best to export from Inventor?
AP214 or AP242. Both contain the product structure with assemblies, parts and quantities, which is what you need for a BOM and a check on the model. AP203 works too, but contains less (for example no colours).
04 Can I view such an export without a CAD licence?
Yes. Open the .stp or .step file in the free STEP viewer on this site: you see the 3D model, the product structure and the BOM, and you can download the BOM as Excel. The file stays on your own computer.
05 Other packages
Working with something else?
From export to demonstrably good release.
Export your STEP from Autodesk Inventor, upload the drawings and the BOM with it and let BOMproof check them against each other. Book a demo with your own design.