Formula and worked example
Material cost = spool price × printed grams ÷ net spool grams.
With a $24 spool containing 1,000 g of filament, a 120 g slicer estimate is 24 × 120 ÷ 1,000 = $2.88.
Assumptions and limits
The worked example assumes the entered grams include supports, brim, purge and other material consumed by this attempt. Enter filament weight only; the empty spool is not part of the denominator. This page estimates material alone, so add labor, machine time, failed attempts and shipping in the full job quote.