Filament cost per print
Quick answer
A 100 cm3 PLA print weighs about 124 g and costs roughly $1.74 in filament from a $14 one kilogram spool. Cost equals volume times density times the price per kilogram, divided by one thousand.
Material densities are published properties, so the mass is a standard calculation. The waste allowance is a convention you can set to zero.
PLA density is 1.24 g/cm3.
Your slicer reports the volume, usually in cubic centimetres or millimetres. One cm3 equals 1000 mm3.
Filament, priced per kilogram
Sorted by price per kilogram, which is the only fair comparison once multipacks are in the mix.
- ELEGOO
ELEGOO ABS 3D Printer Filament 1.75mm Black 1KG Strong Layer Adhesion
$16.99 Check pricePrices change often - Polymaker
Polymaker ABS Filament Black 1KG 1.75mm, Heat Resistant, Strength
$17.10 Check pricePrices change often
Common questions
How do I find the volume of my print?
Every slicer reports it after slicing. PrusaSlicer and OrcaSlicer show the filament used in both grams and cubic centimetres in the sidebar, and Cura shows length in metres, which you can convert with the filament length calculator. If you only have a length, use that tool first and bring the mass back here.
Why does my print cost more than the calculator says?
Three reasons usually explain the gap. Purge and priming waste is higher than you think on multi colour prints, where the purge tower can outweigh the part. Failed prints are rarely counted. And the spool price used is often the multipack price divided incorrectly, so check whether you bought one kilogram or four.
Does infill percentage change the cost?
Yes, and it is the largest single lever you control. The volume figure from your slicer already accounts for the infill you selected, so re-slice at a lower infill and the volume drops directly. Going from 20 percent to 10 percent infill on a chunky part can cut filament use by a quarter.
Is the cheapest filament per kilogram the right buy?
Not always. A spool that jams, snaps or arrives wet costs you far more in failed prints than the few dollars saved, and the failure rate field on this calculator is where that shows up. Price per kilogram is the right way to compare like with like, then weigh that against how consistently the brand prints.
Should I include electricity in the cost of a print?
For a single print it is usually negligible next to the filament, on the order of a few cents for a typical benchtop machine over several hours. It matters when you are running many machines continuously, which is what the print farm throughput calculator covers, and there electricity and labour both start to rival material cost.