3D Printing Cost Calculator FAQ
Every input in SpoolTrak, the free 3D printing cost calculator, explained in plain language — how filament, electricity, printer depreciation, and labor add up to a unit cost, and how the spreadsheet exports work.
Project Details
Project name
Label for the print job — appears in the cost summary and lets you keep prints organized.
Print time (h / m)
Total slicer-estimated printing time. Used for electricity, depreciation, and AMS calculations.
Prep time
Minutes you spend setting up the printer (loading filament, clearing the bed, slicing). Multiplied by your hourly rate.
Post-processing
Minutes spent on the print after it finishes — sanding, painting, deburring, assembly. Multiplied by your hourly rate.
Filament
Filament rows
Add one row per spool / color used in the print. The .gcode or .gcode.3mf import will pre-fill these with the color, type, and weight per filament.
Type
PLA, PLA Matte, PLA Silk, PLA+, PETG, ABS, ASA, or TPU. Metadata for your records — doesn’t affect cost directly.
Weight
Grams of that filament used. Auto-filled from import for Bambu Studio / OrcaSlicer.
Price ($/kg)
Your real spool price per kilogram. Cost = price ÷ 1000 × weight.
Printer
Preset
27 printer presets across Bambu Lab, Prusa, and Creality with real-world PLA-average wattage. Pick one to auto-fill wattage, price, and lifetime.
Wattage
Average power draw during printing — NOT peak. Example, Bambu P1S averages ~105W on PLA, not the 300W default other calculators use.
Electricity rate
Your utility rate per kWh — check your bill. US average is ~$0.16; California can be $0.30+.
Purchase price
What you paid for the printer. Used to amortize depreciation over its lifetime.
Lifetime hours
Realistic total print-hours before the printer needs major work. 5,000–10,000h is typical for consumer FDM.
AMS / MMU
Multi-material unit. Adds its own power draw and depreciation. Default 5.78W per Bambu AMS during active use.
Other Costs
Packaging
Per-unit cost of bags, tissue, hangtags, boxes.
Shipping
Per-unit shipping label / postage if you mail orders.
License
Monthly commercial-license fee (e.g. Patreon designer) divided across the units you sell per month.
Units / Month
How many units you print and sell per month. If you have a monthly license fee, this splits it into a per-unit cost. Also used in the Projects overview for portfolio revenue and profit totals.
Hourly rate
Your labor rate in $/hour. Set to 0 for hobby; set to local minimum wage or higher for selling.
Other cost
Misc. per-unit costs — hardware, inserts, adhesives, extra parts.
Margin & Pricing
Profit margin %
0–99%. Suggested price = totalCost ÷ (1 − margin/100). 30% margin on $2.71 cost = $3.87 sell price.
Suggested price range
We show ±10% around the suggested price as a quick reference for what the market might bear.
Spreadsheet Export
Summary tab
One row per project with the same numbers as the Sales & Profits table: unit cost, sell price, printed, sold, in stock, revenue, fees, and profit.
Activity log tab
Every print and sale entry, newest first. Price is per unit; Fees is the fee charged on that sale; Net = qty × price − fees − qty × unit cost. Import reads this tab to restore your data, so prints rows matter — they rebuild your stock counts.
Inventory tab
Current stock per project: in stock, unit cost, sell price, and value at sell price.
Value at sell price
In stock × sell price — what your shelf stock would bring in if every unit sold at the listed price. Costs aren’t subtracted, so it’s potential revenue, not profit.
Marketplace Fees tab
Your marketplace fee presets (Source, percent, flat $ per unit). On import they merge by name — the file’s values win.
Projects & Filaments tabs
Every calculator setting and filament row, so Import can rebuild a project completely on a new device. Included in both exports — the Sales & Profits file is a complete backup on its own.