Enrichment · Arts & Creativity · Making

What a print really costs,
gram by gram.

Type the weight and time from the slicer and what the spool cost. The calculator gives the cost per copy and for the batch, splits filament from electricity, and tells you how much of the spool it eats.

Cost a printWhat you get

The filament cost calculator

The worked example is made up: four PLA phone stands for a school library. Nothing you type leaves this browser.

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What you get

Enrichment · Arts & CreativityFree

What you finish with
Cost per print and per batch, split into filament and electricity, grams and metres of filament, and copies per spool. It prints as a summary and downloads as a spreadsheet.
Who it is for
Students and makerspace users, teachers running a school 3D printer, and families with a printer at home.
Format
Browser calculator for a phone, tablet or computer, by touch or keyboard. Prints a summary; downloads a spreadsheet (.csv); export and import a file.
Access
Free. No account, no sign-in and nothing to install. Everything you type stays in this browser; nothing is sent to Caveat.
Where it lives
The Arts & Creativity space in Caveat Enrichment.
Support
Questions, a correction or a request: team@caveatacademic.com.

How to use it

  1. Slice the model and note its weight and print time.
  2. Choose the filament and type the spool price and weight.
  3. Add printer power and electricity price if you want power included.
  4. Set an allowance for supports and failures, and the copies.
  5. Read the cost and print the summary.

Cost a print

How the cost is worked out

Filament by weight, power by the hour.

The worked example: a phone standFilament41.0 g38 g + 8% extra× $21.99 ÷ 1,000 g$0.90filament cost4.5 h × 100 W0.45 kWh× $0.17 = $0.08Per print$0.98× 4 = $3.92The worked example: a phone standFilament41.0 g38 g + 8% extra× $21.99 ÷ 1,000 g$0.90filament cost4.5 h × 100 W0.45 kWh× $0.17 = $0.08Per print$0.98× 4 = $3.92
Filament is priced by weight, so the slicer’s gram figure does most of the work; electricity is small for a home printer but grows with long prints.

Filament

Spools are sold by weight, so the slicer’s gram figure times the price per gram gives the material cost. Supports, brims, purge lines and the odd failed print add to it, which is what the extra allowance covers. The length follows from the density: 1.75 mm PLA weighs about 3 grams per metre, so a kilogram spool holds roughly 330 metres.

Electricity

A printer’s power use is mostly its heated bed and nozzle. Energy is power times time: 100 watts for 4.5 hours is 0.45 kilowatt-hours. Multiply by the price per kilowatt-hour from your electricity bill. For short PLA prints this is a few cents; for long prints with a hot bed it can rival the filament.

Sources

  1. NatureWorks. Ingeo biopolymer technical data sheets: PLA density about 1.24 g/cm³ (natureworksllc.com).
  2. U.S. Energy Information Administration. Electric Power Monthly: average retail price of electricity to residential customers (eia.gov).
  3. National Institute of Standards and Technology. Special Publication 811, Guide for the Use of the International System of Units: watt, kilowatt-hour (nist.gov).
  4. U.S. Department of Energy. Estimating appliance and home electronic energy use (energy.gov).

The worked example is made up. Densities are typical; brands differ slightly. Your figures stay in this browser. Support: team@caveatacademic.com.