Why is cost per good part higher than cost per part?

Because the run cost includes setup and every molded part, while the denominator counts only parts that pass. At the defaults, 3,850 dollars of run cost spreads over 9,600 good parts.

Does a lower yield raise or lower cost per good part?

It raises it, because scrap parts carry molding cost into the numerator while good parts shrink in the denominator. The default 96 percent yield gives about 0.40 dollars; 69 percent gives about 0.56.

What does the scrap material cost row include?

The molding cost of every part that failed first inspection. It estimates lost resin and does not add a separate disposal or rework charge.

Should setup cost change with run length?

No. Setup is charged once per run, so a longer run spreads the same setup dollars over more parts and lowers cost per good part.

Toys, Sporting Goods & Recreational Products calculator

Molded Toy Part Cost Calculator

Price a molded toy part on the parts that actually pass inspection. Parts molded, cost per part, first-pass yield and setup go in, and the result carries scrap resin in the run cost.

What this calculator does

Cost per good part across a molded run, the run cost and scrap material, against the cost target the quote must meet.

Formula used

Cost per good part = (parts molded × molding cost per part + mold setup cost) ÷ (parts molded × first-pass yield ÷ 100)
Total run cost = parts molded × molding cost per part + mold setup cost
Good parts = parts molded × first-pass yield ÷ 100
Scrap material cost = parts molded × molding cost per part × (1 − first-pass yield ÷ 100)
Gap to target = target cost per good part − cost per good part, positive under target

Inputs explained

Parts Molded: Parts started in the molding run, from the press schedule.
Molding Cost per Part: Resin, machine time and labor cost of each molded part.
First-Pass Yield: Share of molded parts that pass at the first inspection.
Mold Setup Cost: Setup and tooling cost charged once to this run.
Target Cost per Good Part: Cost per good part the quote must stay under.

How to use the result

Best suited to quoting a new molded toy part, sizing a trial run before tooling release, reviewing yield loss on a mature part.
Scrap resin is priced at molding cost; regrind or resale recovery is not credited. Rework that saves a part is not modeled; only first-pass yield separates good parts. One blended molding cost covers the run.

Common questions

Why is cost per good part higher than cost per part? Because the run cost includes setup and every molded part, while the denominator counts only parts that pass. At the defaults, 3,850 dollars of run cost spreads over 9,600 good parts.
Does a lower yield raise or lower cost per good part? It raises it, because scrap parts carry molding cost into the numerator while good parts shrink in the denominator. The default 96 percent yield gives about 0.40 dollars; 69 percent gives about 0.56.
What does the scrap material cost row include? The molding cost of every part that failed first inspection. It estimates lost resin and does not add a separate disposal or rework charge.
Should setup cost change with run length? No. Setup is charged once per run, so a longer run spreads the same setup dollars over more parts and lowers cost per good part.

Last reviewed 2026-10-01.