CAD & 3D
Mesh Volume Calculator
Calculate the volume of STL, OBJ, and 3MF models online. Measure enclosed 3D volume directly in your browser without uploading files.
Tool
Calculate the volume of STL, OBJ, and 3MF models online. Measure enclosed 3D volume directly in your browser without uploading files.
This tool runs in your browser. Your input is processed locally and is not uploaded.
About this Tool
Use this free online Mesh Volume Calculator to measure the enclosed volume of STL, OBJ, and 3MF models. Load a 3D file, review the detected dimensions and mesh condition, select the correct unit, and calculate the model volume for 3D printing, material estimation, engineering, or manufacturing. Reliable results require a closed and consistently oriented mesh. The calculation runs locally in your browser, so your model does not need to be uploaded to a server.
Examples
- cube-ascii.stl
- multi-group.obj
- multi-object.3mf
Frequently Asked Questions
Which 3D file formats are supported?
The calculator supports STL, OBJ, and 3MF mesh files. These formats describe the model surface using polygons or triangles.
How is the mesh volume calculated?
The model surface is divided into oriented triangles. Their signed contributions are combined to calculate the volume enclosed by the mesh.
Does an STL file contain a unit?
No. STL files store coordinate values but do not define whether those values represent millimeters, centimeters, inches, or another unit. You must select the unit that was used when the model was created.
Why must the mesh be watertight?
A watertight mesh forms a completely closed boundary around a solid region. Holes or missing faces mean that the enclosed space is not clearly defined, which can make the calculated volume inaccurate.
Can inverted faces affect the result?
Yes. Faces with inconsistent orientation can contribute negative volume and reduce or distort the final result. The tool should warn when orientation or mesh-integrity issues are detected.
Can I use the result to estimate material requirements?
Yes. The calculated volume can be used as a starting point for material estimates. Actual consumption may differ because of infill, supports, wall thickness, hollow sections, machining allowances, or manufacturing waste.
Is my model uploaded?
No. The file is read and calculated locally in your browser.