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3DAI
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STL Volume, Weight and Print Cost Calculator

Open an STL to get its exact mesh volume and surface area, then turn them into a weight and a material cost. Pick a material or type your own density, set the infill and wall thickness you print with, and enter your filament or resin price. The formula is shown under the result, so you can see how the estimate is made. Nothing is uploaded.

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How to use it

  1. 1

    Add your STL

    Drop a .stl on the box or click to pick it, and choose the unit it was made in (mm for most files).

  2. 2

    Pick a material

    PLA, PETG, ABS, ASA, TPU, nylon or standard resin, with a typical datasheet density, or enter the density from your own spool.

  3. 3

    Set infill and walls

    Use the infill percentage and wall thickness from your slicer profile. 100% infill gives the solid weight.

  4. 4

    Read weight and cost

    Enter the price per kg to get the cost. The numbers update as you type.

What to know before you convert

  • Volume comes from the triangles and is exact only for closed meshes. The page warns when the mesh has open edges.
  • Weight and cost are estimates. Walls are taken as surface area x wall thickness and the rest of the volume is filled at the infill percentage. Your slicer also adds top and bottom layers, supports, brims and purge, and gives the exact filament use.
  • Densities are typical values from material datasheets: PLA 1.24, PETG 1.27, ABS 1.04, ASA 1.07, TPU 1.21, nylon PA12 1.01 and standard resin 1.1 g/cm³. Brands differ; use the number on your spool or bottle when you have it.
  • Cost covers material only. Electricity, machine time, failed prints and labour are not included.

Don't have a model?

Create one with AI from a photo, a sentence or a sketch. The generators use credits; this converter is free and stays in your browser.

Image to 3D →Turn one photo into a textured 3D model.Text to 3D →Describe an object and get a GLB.Sketch to STL →Draw it, get a printable model.

Frequently Asked Questions

Each triangle and the origin form a small tetrahedron. Adding up their signed volumes gives the volume inside the mesh. It is exact for a closed, watertight mesh and only approximate when the mesh has holes.
Material used = walls + infill. Walls are surface area x wall thickness; the rest of the volume is multiplied by the infill percentage. Weight = material used (cm³) x density (g/cm³). Cost = weight (kg) x price per kg.
Slicers know your exact top and bottom layers, perimeters, infill pattern, supports and brims. This page uses a simpler model so it can run on the STL alone. Treat it as a quick estimate and use the slicer number for quotes.
The density printed on your spool or resin bottle. Without one, the typical values in the material list are a good start: PLA is about 1.24 g/cm³ and ABS about 1.04 g/cm³.
Yes. Choose inches as the unit the STL was made in, otherwise the volume is read as cubic millimetres and comes out about 16,000 times too small.
No. The page reads the file and converts it inside your browser with the open-source three.js library. Nothing is sent to our servers, there is no account, and no credits are used. Closing the tab discards everything.