3D printers run for hours, sometimes days, so it is natural to worry about the power bill. The good news is that a desktop printer uses about as much power as a laptop charger plus a small space heater running a fraction of the time. The details depend on the printer type, the material and whether it is enclosed.
Average power, not peak power
The number on a printer's power supply — 350 W, 500 W — is a maximum, not what it uses. A printer draws the most power while heating the bed at the start of a print. Once the bed and nozzle reach temperature, the heaters only pulse on and off to hold it, and the average draw falls to a fraction of the peak.
| Printer type | Examples | Average while printing |
|---|---|---|
| Entry-level bed slinger | Ender 3, Anycubic Kobra, Prusa MK3S+ | 100–150 W |
| Fast bed slinger | Bambu Lab A1, Prusa MK4S, Ender 3 V3 | 80–120 W |
| Enclosed CoreXY | Bambu Lab P1S / X1C, Creality K1C, Prusa Core One | 120–180 W |
| Large-format FDM | Creality K2 Plus, Neptune 4 Max | 200–300 W |
| Resin MSLA | Elegoo Saturn, Anycubic Photon Mono | 40–80 W |
These are ranges from published measurements and user reports; your printer, room temperature and settings move the number. The calculator uses the middle of each range as its default and lets you type your own value.
The formula
cost = watts × hours ÷ 1,000 × price per kWh
For example, a 4-hour PLA print on a 120 W printer uses 120 × 4 ÷ 1,000 = 0.48 kWh. At $0.18 per kWh that is about 9 cents. The same print on a fast printer that finishes in 2 hours at 100 W uses 0.2 kWh — under 4 cents.
Even at European prices, ten hours of printing on a typical desktop machine costs well under a dollar. Electricity is almost always the smallest line in a print's cost; material and machine wear matter far more. You can see this in the full cost breakdown.
Where the power goes
- Heated bed — the biggest consumer. Holding 60 °C for PLA takes far less power than 100–110 °C for ABS or PC. Large beds use proportionally more.
- Hotend — a 40–60 W heater that holds temperature with short pulses. Higher temperatures and higher flow rates increase its duty cycle.
- Chamber heating — enclosed printers with active chamber heaters can add 100 W or more when printing engineering materials.
- Motors, fans and electronics — typically 10–30 W combined. Fast printers move more, but the effect on average power is modest.
- Standby — a few watts when idle, which adds up if the printer is left on around the clock.
Faster printers can be cheaper to run
Because the heated bed draws power for as long as a print lasts, finishing sooner saves energy. A modern printer that completes a job in half the time at similar wattage uses roughly half the electricity for that job. That is one reason the calculator ties electricity to the estimated print time: change the printer class and both the time and the energy update.
Resin printers
MSLA resin printers have no heated bed and a UV LED array of 30–60 W, so they typically average 40–80 W. Their print time depends on the height of the model, not its volume, and a full build plate takes no longer than a single part. Some models include resin vat heaters that add power in cold rooms. Wash-and-cure stations and heaters add a little more, but they run for minutes rather than hours.
Accessories that use more than the printer
A filament dryer running at 50–70 °C for 6–12 hours can use as much energy as the print itself — a 100 W dryer for 8 hours is 0.8 kWh. Enclosure heaters, air purifiers and space heaters in a cold garage can each outweigh the printer. If you dry filament for every print, include the dryer in your wattage.
How to measure your own printer
The most accurate number comes from a plug-in energy meter or a smart plug with energy monitoring. Plug the printer in, run a typical print from start to finish, and divide the kWh reading by the print hours to get your true average watts. Do this once for PLA and once for your hottest material, then type those figures into the calculator.
Ways to reduce energy use
- Use the lowest bed temperature that still gives good adhesion — often 55 °C instead of 65 °C for PLA.
- Insulate the underside of the bed; cheap cork or foam insulation shortens heat-up and reduces losses.
- Use an enclosure for ABS and ASA instead of a hotter bed.
- Print several parts in one job so the heat-up happens once.
- Switch the printer off rather than leaving it idle overnight.
Want the electricity cost of a specific print? Use the electricity cost calculator, or drop an STL into the print cost calculator to see electricity alongside material and machine time.