3D Printing Weight (Small-Scale) Calculator
Estimate the filament weight, length and material cost for a small 3D print using model volume, infill, shell coverage and filament properties.
Overview
Use this small-scale 3D printing weight calculator to estimate filament use from a model's solid volume, infill setting, shell coverage, material density and filament diameter. It also estimates the filament length and approximate material cost for a single print.
How it works
The calculator first estimates what fraction of the fully solid model will contain plastic. It treats the shell and solid layers as fully filled, then applies the infill percentage to the remaining internal portion. This estimated material volume is multiplied by filament density to calculate weight. The same volume is divided by the filament's circular cross-sectional area to estimate length. Actual slicer output can differ because real part geometry and print settings affect wall and infill volumes.
How to use this calculator
- 1Enter the model's fully solid volume in cm³ from your CAD software or slicer.
- 2Set the infill percentage you plan to use.
- 3Estimate the proportion occupied by walls and solid top and bottom layers.
- 4Enter the density and diameter of your filament.
- 5Add your spool price per kilogram and review the estimated weight, length and cost.
Example Calculation
Solid model volume
50
Infill percentage
20%
Shell and solid-layer share
15%
Filament density
1.24
Filament diameter
1.75
Filament cost per kg
$20
Estimated print weight
19.8 g
With a 15% shell and solid-layer share, the print uses an estimated 16.0 cm³ of PLA, weighing about 19.8 g. This is roughly 6.7 m of 1.75 mm filament and costs about 0.40 in filament.
Frequently asked questions
How do I find my model volume for 3D printing?
Many CAD programs show a part's volume in its properties. You can also import the model into a slicer, although the slicer's reported filament volume or weight is normally more useful for the final estimate.
What density should I use for PLA filament?
A typical PLA density is about 1.24 g/cm³. Check the filament manufacturer's technical data sheet when available, as blends and additives can change density.
Why is the estimated weight different from my slicer?
Slicers calculate the actual toolpath, including wall count, top and bottom layers, infill pattern, line width and model geometry. This calculator uses a simplified shell-share estimate, so it is best used for planning.
Does infill percentage equal the percentage of a model's total volume that is plastic?
Not usually. Walls and solid top and bottom layers are often fully filled, so the total plastic share is higher than the infill percentage alone.
Does this include supports and rafts?
No. Add the expected support, brim, raft and purge material separately, or use your slicer's final estimate when those features are enabled.
How accurate is the filament length estimate?
It is based on the estimated plastic volume and the stated filament diameter. It is useful for spool planning, but the actual length can vary with slicer settings and diameter tolerance.
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Assumptions and warnings
Assumptions
- The solid model volume is accurate and measured in cubic centimetres.
- Shell and solid-layer share is an estimate of the model volume occupied by walls, top layers and bottom layers.
- Filament density is uniform throughout the print.
- The estimate excludes purge material, skirts, brims, rafts, supports, failed prints and spool waste.
- Material cost covers filament only and excludes electricity, machine time and other costs.
Warnings
- This calculator provides an estimate only; use your slicer's filament estimate for a print-specific result.
- Support structures, brims, rafts, infill pattern, wall count and slicer settings can materially change actual filament use.