MundoKit

3D Print Filament Cost Calculator

Enter print grams and your spool price for a quick material cost. Change spool mass or add supports, purge and failed-print grams when needed.

Inputs
currency
g
g
g
g
g

Results

Total filament cost
2.00 currency units
Total material
100 g
Cost per gram
0.02 currency/g
Material cost breakdown
MaterialCost
Model2.00 currency units
Supports0.00 currency units
Purge0.00 currency units
Failed attempts0.00 currency units
  • Use one currency. Enter only material not already counted in the model mass: slicer totals may already include supports and purge.
  • Failed-print mass is actual additional material, not a failure probability. Electricity, machine wear, labor, tax and profit are excluded.

Results update as you type. The share link stores your inputs after the # in the address, which is not sent to our server, but anyone you send it to can read them.

How it works

Prusa’s filament calculator allocates spool cost using net filament weight and print weight. This tool uses the same proportional material-cost method without labor or machine pricing.

Cost per gram = spool price ÷ net filament grams Total grams = model + additional supports + additional purge + failed-attempt material Material cost = total grams × cost per gram

Net spool mass excludes the empty spool. Extra material is additive: if your slicer’s mass already includes supports or purge, leave those fields at zero to avoid double counting. Failed material means actual additional grams used, not an expected failure rate.

All prefilled prices, loads and performance assumptions are hypothetical examples. Use one currency throughout. Calculations keep full precision internally; displayed energy and money are rounded, and year-end payback is shown in whole years where applicable.

Worked examples

Simple material-only print

At 20 per 1,000 g spool, a 100 g model costs 2.00. Cost per gram is 0.02.

Supports, purge and a failed attempt

The same spool with a 100 g model, 20 g supports, 30 g purge and 50 g failed material uses 200 g total and costs 4.00. The extra material costs 0.40, 0.60 and 1.00 respectively.

Frequently asked questions

Does spool weight include the spool?
No. Use net filament mass. A spool advertised as one kilogram of filament normally describes material mass; verify the product label.
Should I add supports separately?
Only if the entered model mass excludes them. Many slicer totals already include support material.
What about multi-material purge?
Enter additional purge grams that are not already in your model or support total. For different filament prices, calculate each material separately.
Does it include electricity or labor?
No. It is a material-only calculator and does not set a selling price.
Can I enter failed-print material?
Yes. Enter the actual grams wasted on attempts before the successful model. No probability or automatic retry multiplier is assumed.

Sources

Last reviewed 2026-11-14. The method is written out above so you can check our math.