Injection molding · Costing
Material Cost Per Part Calculator
Estimate resin material cost per molded part. This practical tool is an engineering estimate—validate decisions against machine, material, mold, and process data.
Decision chain
From estimate to the next check
- Mass boundaryPart and runner mass allocated by cavity
- Material policyPurchase price and recovery or scrap rule
- Material resultA resin-only exposure per part
- Commercial scopeAdd conversion, quality, tooling, and logistics separately
Formula and method
Allocated resin mass × resin price, adjusted for unrecovered scrap.
Inputs and units
Enter measured or specified values in the displayed units. Keep units consistent; results are rounded for practical planning. This first release uses the displayed engineering units rather than a unit-switcher.
Worked example
(45 g + 12 g ÷ 2 cavities) ÷ 1,000 × $2.40/kg × 1.03 scrap = $0.13 per part.
Define the material boundary first
Use weighed or validated part and runner mass, the actual cavity allocation, purchase price per kilogram, and an explicit unrecovered-scrap rule. Record whether regrind is recovered, sold, or discarded rather than hiding it in a percentage.
Keep material cost separate from conversion cost
This result excludes press time, labor, energy, inspection, packaging, logistics, and margin. Pair it with a validated cycle and supplier cost model before using it as a quotation input.
Sanity check price sensitivity
Changing resin price or unrecovered scrap should change the result in the expected direction. If a small mass change has no visible effect, use more precision before making a commercial decision.
Interpretation, assumptions, and limitations
FAQ
Can this be presented as a finished part price?
No. It is a material-only component. A finished price needs defined conversion, quality, post-process, logistics, tooling, and commercial assumptions.