Trust

Methodology

Every number this site produces is a transparent estimate built from the formulas below, using the inputs you provide. Nothing is a guarantee of print success, dimensional accuracy, strength, safety or delivery time. The current formula version is v1.1.0, stamped into every calculation, and this page was last verified against the implementation on 25 July 2026.

The formulas

cost/gram   = spool_price ÷ (spool_weight_g × (1 − waste))
material    = grams_used × cost/gram

cost/mL  = price_per_litre ÷ 1000
resin    = mL_used × cost/mL
total    = resin + IPA + gloves + FEP_wear

energy_kWh  = average_watts ÷ 1000 × print_hours
energy_cost = energy_kWh × rate_per_kWh

depreciable   = purchase + lifetime_maintenance − residual
cost_per_hour = depreciable ÷ useful_print_hours
machine_cost  = cost_per_hour × print_hours

labour = Σ(minutes_by_task ÷ 60 × hourly_rate)

reserve = repeatable_cost × p ÷ (1 − p)

hourly: job_overhead = (monthly_overhead ÷ billable_hours) × print_hours
explicit: per-order and per-unit lines entered directly

margin price = (cost + fixed_fee) ÷ (1 − percentage_fee − margin)
markup price = (cost × (1 + markup) + fixed_fee) ÷ (1 − percentage_fee)
margin = profit ÷ price      markup = profit ÷ cost

tax_amount = final_price × tax_rate
gross      = final_price + tax_amount   ← what the customer pays

tier_total     = one_time_order_cost + quantity × per_unit_cost
tier_unit_cost = tier_total ÷ quantity

Rounding & currency

Calculations run in plain numbers and round only at the currency boundary, using round-half-up to minor units (cents). This avoids the binary-float drift that makes naive Math.round(x*100)/100 mis-round values like 1.005. The calculators support arbitrary currencies; conversions are yours to supply, since live exchange rates are intentionally out of scope.

File parsing & accuracy

G-code is the truthful source for estimated print time and filament usage; the parser reads the slicer’s own header comments (Cura, PrusaSlicer, OrcaSlicer, Bambu Studio, SuperSlicer), attributes the slicer, and records the exact lines it used. STL and 3MF files provide geometry only — volume via the divergence theorem and a bounding box — and are labelled a geometry estimate; for 3MF the declared model unit and build transforms are applied before any figure is reported. Non-watertight meshes are detected and flagged because their volume is unreliable. Files are parsed entirely in the browser and never uploaded.

Sources & limitations

• The failure-reserve formula is the standard expected-value result for retries until success (expected attempts = 1 ÷ (1 − p)).
• Marketplace fee presets (e.g. Etsy) are dated and sourced but editable, because rates change and vary by account and region. They are a starting point, never an authority.
• Material densities and default rates are illustrative, and the printer power-draw presets (sourced above) are averages or nameplate maxima. Replace them with measured values for a quote you intend to send.
• This is not tax, legal, structural, medical or accounting advice, and it does not predict whether a part is fit for any purpose.

Sales tax / VAT presets

The tax presets are standard rates, last verified 2026-07-25. The default is always “none / not registered” — no one is opted into a rate they did not choose, and whether you must charge VAT or sales tax depends on your registration and jurisdiction. Sources: GOV.UK — VAT rates and European Commission — VAT rates applied in EU member countries. This tool does not give tax advice — confirm the rate that applies to you.

Preset sources

Every preset offered in the tools is dated and sourced, and editable — a preset is a starting point, never an authority. All were last verified 2026-07-25.

Printer power-draw presets

“Measured” figures are manufacturer-measured averages while printing; “max (nameplate)” figures are rated input power — real printing draw sits below the rating, so those presets are marked approximate in the tool. Measured averages are material-dependent (a hotter bed and chamber for ABS draws more than PLA).

Electricity rate presets

The EIA figure is a preliminary monthly average; the Ofgem cap is revised quarterly (the rate shown expires 30 September 2026). Your own tariff beats either.

Marketplace fee presets

The Etsy US preset (6.5% transaction fee, 3% + $0.25 payment processing, $0.20 listing fee) is sourced from the Etsy Fees & Payments Policy and last verified 2026-07-25. Fees vary by account, region and time — every field is editable.

Change log

Questions about a formula? The pricing guide works through them with numbers, and the privacy page covers how your data is handled.