Why divide the cost by the changeover minutes?

The same dollars over a shorter changeover is a higher cost per minute, which makes changeovers of different lengths comparable. Both figures divide this changeover's own total, so the bases never mix.

What counts as a missed unit during a changeover?

Units the line would have run during the changeover minutes at its running rate. Use the rate sustained before the changeover, not a nameplate or sales figure.

Should expedite freight count as an adder?

Only freight the changeover caused, such as expediting late output. Ordinary inbound or outbound freight belongs in normal cost, not in this event.

How do I get contribution value per unit?

Ask cost accounting for selling price less variable material, energy and labor. Fixed overhead does not disappear when one fewer unit is made, so leave it out.

Conveyors calculator

Changeover Impact on Line Capacity Calculator

Price a changeover in the output it lost and the labor, setup and startup dollars it spent. Enter the missed units, contribution per unit, setup cost, adders and the changeover minutes.

What this calculator does

What a changeover costs the line in lost contribution and setup dollars, per changeover, per missed unit and per minute.

Formula used

Lost contribution = units not produced during the changeover × contribution value per missed unit
Setup and startup adders = changeover labor and setup cost + startup scrap or expedite adders
Changeover capacity impact cost = lost contribution + setup and startup adders
Cost per missed unit = total changeover cost ÷ units missed in that same changeover
Cost per changeover minute = total changeover cost ÷ that changeover's minutes

Inputs explained

Units Not Produced During Changeover: Good units the line would have made during the changeover.
Contribution Value per Missed Unit: Selling price minus variable cost for each missed unit.
Changeover Labor and Setup Cost: Crew labor and setup cost charged to the changeover.
Startup Scrap or Expedite Adders: Startup scrap and expedite costs the changeover caused.
Changeover Duration: Last good part to first good part, timed on this line.

How to use the result

Best suited to pricing a product change on the line, building the case for a SMED project, comparing changeover cost across lines.
Prices one changeover; a product change that runs several changeovers needs its own analysis. Leaves out sales lost when the changeover delays a customer order.

Current U.S. benchmarks

The U.S. has 21,668 machinery manufacturing establishments employing about 1,086,146 workers (Census County Business Patterns, 2023).

Common questions

Why divide the cost by the changeover minutes? The same dollars over a shorter changeover is a higher cost per minute, which makes changeovers of different lengths comparable. Both figures divide this changeover's own total, so the bases never mix.
What counts as a missed unit during a changeover? Units the line would have run during the changeover minutes at its running rate. Use the rate sustained before the changeover, not a nameplate or sales figure.
Should expedite freight count as an adder? Only freight the changeover caused, such as expediting late output. Ordinary inbound or outbound freight belongs in normal cost, not in this event.
How do I get contribution value per unit? Ask cost accounting for selling price less variable material, energy and labor. Fixed overhead does not disappear when one fewer unit is made, so leave it out.

Last reviewed 2026-10-01.