3D Print Cost Calculator

Most people cost a print by weighing it and multiplying by the filament price. That gets you maybe half the real number.

The full cost has four parts. Filament is the obvious one. Electricity is the one people overestimate — a printer drawing 150 watts for five hours uses 0.75 kWh, which is about thirteen cents. Machine wear is the one people forget: a printer that cost four hundred and lasts four thousand hours costs ten cents an hour to own. And failures are the one people refuse to count, even though a print that fails at hour nine consumed real filament and real time.

The failure adjustment is the part worth understanding. If one print in ten fails, only nine of every ten you start actually ship — so each shipped print has to carry the cost of the tenth. That means dividing by 0.9, not adding 10%.

1. Step 1 Filament material = weight_g ÷ 1000 × price_per_kg
2. Step 2 Electricity energy = watts ÷ 1000 × hours × price_per_kWh Use measured draw, not the power supply rating — printers idle far below it.
3. Step 3 Machine wear depreciation = printer_price ÷ lifetime_hours × hours
4. Step 4 Spread the failures cost = (material + energy + depreciation) ÷ (1 − failure_rate) Divide, do not add. A 10% failure rate raises cost by 11.1%, not 10%.
5. Step 5 Add your time total = cost + (hands_on_minutes ÷ 60 × your_rate)
6. Step 6 Work back from the margin price = total ÷ (1 − margin%) Margin is a share of the selling price, which is why you divide rather than multiply.

Example: a 45 g print over 5 hours on 20 per kg filament is 0.90 in material, 0.13 in electricity and 0.50 in machine wear. That is 1.53, or 1.70 after a 10% failure rate. Add 15 minutes at 20 an hour and the true cost is 6.70 — sell at 11.17 for a 40% margin.

• Electricity is calculated from average draw across the whole print. Real consumption is higher during bed heat-up and lower during long travel-free stretches, but the average over a multi-hour print is close.
• Printer depreciation is straight-line across the stated lifetime hours. It does not account for the resale value of a working machine, which makes this figure slightly conservative.
• The failure rate is applied by dividing rather than adding, because failures reduce the number of prints that actually ship. It assumes failures happen at an average point in the print, so a machine that mostly fails in the first layer is being over-charged here.
• Consumables beyond filament — nozzles, build plates, adhesion sticks, isopropyl — are not itemised. They typically add 3–8% to material cost.
• Marketplace fees are not included in the suggested price. Etsy takes about 9.5% including payment processing, eBay 12–13%, and a personal website takes payment processing of around 3%.
• Labour is your hands-on time only. Print time is machine time and should not be billed at your hourly rate — that is what depreciation covers.
• Margin is expressed as a share of the selling price, which is the standard retail convention. A 40% margin means 40 cents of every dollar taken is profit, not that you marked cost up by 40%.
• Filament price assumes you use the whole spool. Partial spools and colour changes waste more than most people account for.