Why is yield loss applied after downtime?

Yield loss only bites on units the line actually runs. At 15% downtime, only 850 of 1,000 gross units reach the process, so a 5% yield loss costs 42.5 units, not 50. Applying both rates to gross capacity overstates the loss.

Is the gap the same as missing demand?

Yes, a negative gap is the units demand wants and the line cannot ship on the current loss rates. Positive means spare capacity. Compare it with the forecast for the same period, not an annual average.

Which loss should I attack first?

Start with the larger loss row. Downtime usually yields to reliability and changeover work, while yield loss yields to process control and inspection. Fix the bigger one first, then remeasure, because the two losses move together.

Does gross capacity include breaks and lunches?

No. Use the capacity the line is scheduled to run, with breaks and planned stops already removed. Counting them inflates gross capacity and makes both loss percentages look smaller than they are.

Lean Manufacturing & Operations calculator

Capacity Gap Analysis Calculator

Measure what a line can actually ship once downtime and scrap take their share, then compare it with demand. Enter gross capacity, both loss rates and the demand for the period.

What this calculator does

Good capacity after downtime and yield losses, with each loss priced and the gap against demand.

Formula used

Capacity lost to downtime = gross capacity × uptime loss ÷ 100
Capacity lost to scrap and rework = gross capacity × (1 − uptime loss ÷ 100) × yield loss ÷ 100
Good output capacity = gross capacity − downtime loss − scrap and rework loss
Total capacity lost = gross capacity − good output capacity
Capacity gap versus demand = good output capacity − demand

Inputs explained

Gross Theoretical Capacity: Rated output the line could make with no losses.
Uptime Loss: Share of scheduled time stopped, from downtime records.
Yield Loss: Share of started units scrapped or reworked.
Demand: Units the plan needs in the same period.

How to use the result

Best suited to sizing capacity before a launch, testing a supplier recovery plan, budgeting reliability improvements.
The two losses interact, so remeasure both after a reliability or quality change. Gross capacity assumes no mix or changeover penalty beyond the loss rates entered.

Current U.S. benchmarks

U.S. manufacturing runs at 75.7% of capacity (Federal Reserve, Aug 2026). New factory orders are up 8.5% year over year (Census).

Common questions

Why is yield loss applied after downtime? Yield loss only bites on units the line actually runs. At 15% downtime, only 850 of 1,000 gross units reach the process, so a 5% yield loss costs 42.5 units, not 50. Applying both rates to gross capacity overstates the loss.
Is the gap the same as missing demand? Yes, a negative gap is the units demand wants and the line cannot ship on the current loss rates. Positive means spare capacity. Compare it with the forecast for the same period, not an annual average.
Which loss should I attack first? Start with the larger loss row. Downtime usually yields to reliability and changeover work, while yield loss yields to process control and inspection. Fix the bigger one first, then remeasure, because the two losses move together.
Does gross capacity include breaks and lunches? No. Use the capacity the line is scheduled to run, with breaks and planned stops already removed. Counting them inflates gross capacity and makes both loss percentages look smaller than they are.

Related guides

Last reviewed 2026-10-01.