Free STEP viewer
Open STEP and STP files online

Open a STEP or IGES file from SolidWorks, Fusion 360, Inventor, Creo or Onshape. See every part, measure in millimetres and check the size and volume.

Nothing is uploaded: the file is opened on your own computer.

Drop a STEP file here or choose a file. STEP (.step, .stp) and IGES (.igs, .iges), AP203, AP214 and AP242. IFC, STL, OBJ and FBX files open too.

Save a copy as

Your file stays on your computer. It is opened in this browser tab and is never uploaded to us or anyone else.

Every part of an assembly listed, each one can be hidden
Measure between 2 points in millimetres
Size, volume and a watertight check for each model

How it works

How to open a STEP file online

3 steps, and the file never leaves your computer.

1. Open the STEP file

Drop the .step or .stp file on the viewer or click to choose it. The solid is turned into a fine mesh in your browser, which takes a few seconds for a large assembly.

2. Look through the parts

The side panel lists every part of the assembly. Untick a part to hide it and see what is behind it, or click a part in the model to see its size.

3. Measure and save

Use Measure to get the distance between 2 points in millimetres. Save a copy as STL for printing, or as GLB or OBJ for other 3D programs.

What you can check

What the STEP viewer shows you

Enough to check a part or an assembly without opening a CAD program.

The parts of an assembly

Each solid in the file is listed by the name the CAD program gave it. Parts with the same name are counted together, so 12 identical bolts show as one line.

Sizes in millimetres

STEP files carry their units, and the viewer converts them to millimetres. The overall size is shown for the model and for any part you click.

Volume and weight

For a closed solid the viewer shows the volume in cubic centimetres and the weight of a solid PLA print, which is a quick first check before a prototype is printed or quoted.

STEP, STP and IGES

STEP and STP are the same format with 2 file extensions. IGES is its older cousin and opens the same way. AP203, AP214 and AP242 files are all read.

Export to STEP

How to export STEP from SolidWorks, Fusion 360, Inventor, Onshape and Creo

Every CAD program can save STEP. These are the menu steps.

SolidWorks

Choose File > Save As, pick STEP AP214 (*.step) or STEP AP242 as the file type and click Save. Use Options to include or leave out hidden parts.

Fusion 360

Choose File > Export, pick STEP Files (*.stp) as the type and click Export. The file is prepared in the cloud and saved to your computer.

Autodesk Inventor

Choose File > Save As > Save Copy As, pick STEP Files (*.stp) as the type, and set the application protocol under Options.

Onshape and Creo

In Onshape, right-click the Part Studio or Assembly tab and choose Export, then STEP. In Creo, choose File > Save As > Save a Copy and pick STEP.

From CAD file to images

What we make from STEP files

Product designers and manufacturers send us their CAD files to be turned into images that sell the product before the first one is made.

3D product rendering

Photoreal studio and lifestyle images of your product for catalogues, web shops and launches, made directly from the STEP file.

See product rendering

3D modeling

Clean models built from drawings, sketches or a rough mesh, when there is no CAD file yet.

See 3D modeling

Architectural visualization

Photoreal images of buildings and interiors, with your product placed in them where it belongs.

See architectural visualization

STEP viewer FAQ

Questions about viewing STEP files

File versions, faceted curves, assemblies and what the viewer can and cannot do.

Ask us a question

What is the difference between STEP and STP?

None. .step and .stp are 2 extensions for the same ISO 10303 format, and both open here. The version inside the file, AP203, AP214 or AP242, matters more than the extension, and the viewer reads all 3.

Why do curved surfaces look slightly faceted?

A STEP file stores exact curves, and every viewer turns them into small flat triangles to draw them. This viewer uses a fine setting, 0.1% of the model size, so the facets only show when you zoom right in. The file itself is not changed.

Can I see the structure of an assembly?

Every solid is listed as a part, with the name from the CAD program, and can be hidden or shown. The nesting of sub-assemblies is not shown as a tree; parts with the same name are grouped instead.

Can it open IGES files?

Yes. .igs and .iges files open the same way as STEP. IGES often stores surfaces rather than closed solids, so the watertight check can say No for a model that looks complete.

Can I edit or dimension the model?

No. The viewer shows, measures and saves a copy of the model in other formats. Edits and drawings with dimensions belong in your CAD program.

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