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3DAI
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STL Weight Calculator: How Much Filament Will It Use?

Before you slice, find out roughly how heavy a print will be and whether the spool on your printer has enough left. Drop the STL, choose the material and the infill and wall settings you print with, and read the weight in grams, the filament length in metres and the material cost. The file stays on your device.

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How to use it

  1. 1

    Drop the STL

    Add a .stl and pick the unit it was modelled in. Most files are in millimetres.

  2. 2

    Choose the filament

    PLA, PETG, ABS, ASA, TPU or nylon with its typical density, or type the density printed on your spool.

  3. 3

    Match your slicer

    Enter the infill percentage and wall thickness from your print profile. Use 100% for the weight of a solid part.

  4. 4

    Read grams and metres

    See the estimated weight, the length of 1.75 mm and 2.85 mm filament, and the cost once you add the price per kg.

What to know before you convert

  • Weight is an estimate from the mesh alone: the walls are surface area times wall thickness and the inside is filled at your infill. Supports, brims, rafts and purge are not counted, so add a margin for those.
  • The mesh must be closed for an exact volume. Open edges are reported, and the weight is then approximate.
  • Filament length assumes the nominal 1.75 mm or 2.85 mm diameter; real filament varies by a few percent. Length is not shown for resin.
  • Typical densities in g/cm³: PLA 1.24, PETG 1.27, ABS 1.04, ASA 1.07, TPU 1.21, nylon PA12 1.01. The value on your spool is better when you have it.

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

An STL has no weight, only a shape. Its volume is worked out from the triangles, then multiplied by the density of the material. For a printed part, only the walls are solid and the inside is partly filled, so the weight depends on your infill and wall settings too.
Divide the material volume by the cross-section of the filament. A 1.75 mm strand is about 2.4 mm² across, so 1 kg of PLA is roughly 335 m and 1 g is about 0.33 m. The page does this for 1.75 mm and 2.85 mm filament.
Weigh the spool, subtract the empty spool weight printed on the label or the maker website, and compare with the estimate here. Leave 10% to 15% extra for supports, brims and the purge line.
The slicer knows your exact top and bottom layers, perimeters, infill pattern and supports. This page uses a simpler model so it can work from the STL alone. It is close for most parts; the slicer has the final number.
Choose inches as the unit before reading the result. An inch model read as millimetres comes out about 16,000 times too light.
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.