How do you calculate production plan variance?

Subtract actual completed units and any authorized plan adjustments from the planned target. With 200 planned, 175 actual, and 10 authorized, the unexplained variance is 200 - 175 - 10 = 15 units.

What counts as an authorized plan adjustment?

Any reduction management formally approved — a cancelled or pulled-forward order, scheduled maintenance signed off in advance, or an engineering hold. These are subtracted so they don't masquerade as floor underperformance.

What's the difference between total gap and unexplained variance?

Total gap is planned minus actual (185 in the example), the full shortfall. Unexplained variance nets out the 10 authorized units, leaving 15 that still need a root cause.

Is a positive variance good or bad?

A positive unexplained variance means you built fewer units than plan even after approved changes — that's a loss to investigate. Zero means the floor fully explained the miss.

Why net out adjustments instead of using raw gap?

Raw gap punishes the floor for office decisions. If 10 units were dropped by an approved order pull, charging the line for all 185 short hides the real 15-unit problem worth fixing.

How does this relate to schedule attainment rate?

Attainment gives the percentage achieved; plan variance gives the unit shortfall and isolates the unexplained portion. Use variance when you need to assign a corrective action to a specific gap.

Lean Manufacturing & Operations calculator

Production Plan Variance Calculator

Production plan variance is the unit gap between what you scheduled and what you built, after stripping out approved changes so you see only the unexplained shortfall. Schedulers, supervisors, and continuous-improvement teams use it to separate misses that management already signed off on (a pulled order, an approved downtime) from misses that need root-cause analysis. It matters because a raw gap-to-plan blames the floor for decisions made in the office; netting out authorized adjustments points accountability at the real loss. This is the number that drives corrective-action tickets, not just a dashboard color.

What this calculator does

Calculate the variance between planned and actual production output to quantify schedule deviations and identify improvement areas.
Use this calculator to measure the gap between plan and actual, broken down by shift or day, to identify patterns in schedule misses and drive corrective action.
It computes the unexplained variance by subtracting actual output and authorized adjustments from the planned target, plus the total raw gap from plan.

Formula used

Unexplained Variance = Planned - Actual - Authorized Adjustments

Inputs explained

Planned production target:
Actual production completed:
Authorized plan adjustments:

How to use the result

Use it after a shift or run when actual fell short of plan and you need to know how much of the miss is genuinely unaccounted for.
It's only as honest as your adjustment log — if approved changes aren't recorded, legitimate reductions show up as unexplained variance and trigger false alarms.

Current U.S. benchmarks

U.S. manufacturing runs at 75.6% of capacity (Federal Reserve, May 2026). New factory orders are up 2.3% year over year (Census).

Common questions

How do you calculate production plan variance? Subtract actual completed units and any authorized plan adjustments from the planned target. With 200 planned, 175 actual, and 10 authorized, the unexplained variance is 200 - 175 - 10 = 15 units.
What counts as an authorized plan adjustment? Any reduction management formally approved — a cancelled or pulled-forward order, scheduled maintenance signed off in advance, or an engineering hold. These are subtracted so they don't masquerade as floor underperformance.
What's the difference between total gap and unexplained variance? Total gap is planned minus actual (185 in the example), the full shortfall. Unexplained variance nets out the 10 authorized units, leaving 15 that still need a root cause.
Is a positive variance good or bad? A positive unexplained variance means you built fewer units than plan even after approved changes — that's a loss to investigate. Zero means the floor fully explained the miss.
Why net out adjustments instead of using raw gap? Raw gap punishes the floor for office decisions. If 10 units were dropped by an approved order pull, charging the line for all 185 short hides the real 15-unit problem worth fixing.

Last reviewed 2026-05-12.