The short answer: most hobby prints cost 1 to 5 cents per gram all-in, and the filament is 70–85% of that. A 50 g PLA part printed in four hours costs about $1.10 at US prices. The long answer depends on five things, and only two of them show up in most online calculators.
The five costs
- Filament. Price per kilogram divided by 1,000, times grams. Budget PLA at $18/kg is 1.8¢ per gram; PETG at $22/kg is 2.2¢; carbon-fibre nylon at $60/kg is 6¢.
- Electricity. Average watts × hours ÷ 1,000 × your tariff. A Bambu A1 mini averages about 80 W, an Ender 3 about 110 W, an enclosed X1 Carbon printing ABS about 150 W. At the 2026 US average of $0.17/kWh, that is 1–3 cents per hour. Electricity is almost never the expensive part.
- Printer wear. A $400 printer that lasts 5,000 printing hours costs 8¢ per hour before you buy a single nozzle. Add nozzles, belts, PEI sheets and fans and 10–15¢ per hour is realistic for a busy machine.
- Failures. If one print in ten fails, every successful print really costs 1 ÷ 0.9 = 1.11× its nominal cost. New users run 10–20% failure rates; dialled-in machines 2–5%.
- Your time. Slicing, bed prep, removal, support cleanup. Even at ten minutes per print, a $15/hour rate adds $2.50, which dwarfs the filament for small parts. Hobbyists ignore this; anyone selling prints cannot.
Three worked examples
| Keychain | Phone stand | Full-size helmet | |
|---|---|---|---|
| Filament | 12 g PLA, $0.22 | 150 g PETG, $3.30 | 950 g PLA, $17.10 |
| Time | 35 min | 5 h | 42 h |
| Electricity (110 W, $0.17) | $0.01 | $0.09 | $0.79 |
| Wear (10¢/h) | $0.06 | $0.50 | $4.20 |
| 5% failure allowance | $0.02 | $0.20 | $1.16 |
| True cost | $0.31 | $4.09 | $23.25 |
Notice that for the helmet, wear and failures together cost more than the electricity by a factor of six. That is the usual pattern on long prints.
What people get wrong
- Using the power supply rating. A 350 W supply does not mean 350 W of consumption. Beds cycle on and off; the average is a third to half of the rating. Our printer pages list measured averages.
- Forgetting the spool is not 1 kg of filament. Many spools are 750 g or 500 g net, and the “1 kg” on a budget listing is sometimes gross weight.
- Pricing at “cost × 2” for sales. Marketplace fees come off the top. Etsy takes about 9.5% plus fixed fees on item and shipping; eBay about 13.6%. Use the seller pricing tool to solve the price backwards from the profit you want.
Run your own numbers in the 3D print cost calculator. The URL updates as you type, so you can bookmark a profile per printer.