How do you calculate prototype build cost?

Multiply units by per-unit cost by build yield, then add soft tooling and setup. For 25 units at $320, 80% yield, and $6,500 tooling the total is $12,900.

Why is my cost per usable prototype so much higher than the per-unit quote?

Because fixed tooling spreads across few units and yield loss means you pay for parts you can't use. Here the $320 quote becomes $516 per usable prototype once tooling and yield are included.

What is a reasonable build yield for prototypes?

Early prototype yields of 70-85% are common because processes aren't dialed in; the 80% used here is typical for a second or third prototype round.

Should soft tooling be amortized over prototypes or production?

For a true prototype-phase budget, charge it to the prototypes as this model does. If the tool carries into pilot, amortize across the larger volume separately.

Prototype build cost vs pilot run cost?

Prototype cost covers a small design-validation build, often on soft tooling; pilot run cost covers a larger near-production build that proves the line. Per-unit cost typically drops sharply from prototype to pilot.

How many extra prototypes should I build for yield loss?

Divide the usable units you need by your expected yield. At 80% yield you build roughly 1.25 units for every usable one you require.

NPI, DFM/DFA & Engineering Change calculator

Prototype Build Cost Calculator

Prototype Build Cost tells an NPI team what a round of prototypes actually costs once yield losses and soft tooling are folded in. Design and program managers use it to set realistic prototype budgets before committing to a build, and to compare quotes from prototype shops on an apples-to-apples basis. It matters because prototype overspend is a common, quiet drain on NPI budgets — a 25-piece build with a few scrapped units and a soft tool can cost far more per usable part than the headline per-unit price. This calculator surfaces both the total and the true cost per usable prototype.

What this calculator does

Estimate the cost of a prototype build run including per-unit material and labor plus the one-time soft tooling to produce them.
A design engineer budgeting a prototype run to validate a new part ahead of committing to production tooling.
It combines variable build cost (units x per-unit cost x yield) with fixed soft tooling to produce total prototype build cost and cost per usable unit.

Formula used

Prototype build cost = prototype units x cost per unit x build yield% + soft tooling setup
Cost per usable prototype = total build cost / prototype units built

Inputs explained

Prototype Units Built:
Cost Per Prototype Unit:
Build Yield:
Soft Tooling & Setup:

How to use the result

Use it when scoping a prototype phase, comparing prototype-shop quotes, or deciding how many extra units to build to cover yield loss.
It applies a single flat yield to the whole build; staged builds where yield improves run to run are better modeled in separate rounds.

Common questions

How do you calculate prototype build cost? Multiply units by per-unit cost by build yield, then add soft tooling and setup. For 25 units at $320, 80% yield, and $6,500 tooling the total is $12,900.
Why is my cost per usable prototype so much higher than the per-unit quote? Because fixed tooling spreads across few units and yield loss means you pay for parts you can't use. Here the $320 quote becomes $516 per usable prototype once tooling and yield are included.
What is a reasonable build yield for prototypes? Early prototype yields of 70-85% are common because processes aren't dialed in; the 80% used here is typical for a second or third prototype round.
Should soft tooling be amortized over prototypes or production? For a true prototype-phase budget, charge it to the prototypes as this model does. If the tool carries into pilot, amortize across the larger volume separately.
Prototype build cost vs pilot run cost? Prototype cost covers a small design-validation build, often on soft tooling; pilot run cost covers a larger near-production build that proves the line. Per-unit cost typically drops sharply from prototype to pilot.

Last reviewed 2026-05-12.