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Earned Value Schedule Variance and SPI Calculator

Compare earned value with planned value to measure schedule performance in budget-value terms. The result is not a delay measured in days, and both inputs must describe the same status date.

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Your numbers

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How the calculation works

Compare budgeted value earned from completed work with work planned by a project status date. Schedule variance measures the gap in budget-value units, while the schedule performance index expresses their ratio.

Schedule variance SV = EV − PV. Schedule performance index SPI = EV / PV when PV is positive.

  1. Establish a common baseline

    Select one project scope and status date. Completed and planned work need comparable budget valuation before either subtraction or division can produce a meaningful comparison.

  2. Calculate schedule variance

    Subtract planned value from earned value. A negative amount means less budgeted work has been earned than planned; a positive amount means more has been earned.

  3. Calculate the index

    Divide earned value by positive planned value. One means the values match. With zero planned value, variance remains calculable but the ratio is undefined.

Worked example: Behind plan

Sample inputs demonstrate the method. They are not a forecast or product offer.

Earned value of €80,000 against €100,000 planned value gives a variance of minus €20,000. The ratio is 0.8, meaning earned budget value is 80% of the planned amount at that date.

Earned value (EV)
80000
Planned value (PV)
100000

Expected result

Schedule variance
-€20,000.00
Schedule performance index
0.8
Worked example: Ahead of plan

Sample inputs demonstrate the method. They are not a forecast or product offer.

Earned value (EV)
120
Planned value (PV)
100

Expected result

Schedule variance
€20.00
Schedule performance index
1.2

Understanding your result

Variance uses the project's budget currency. It cannot directly give days late because planned work and its budget value are not necessarily distributed evenly through time.

An index below one indicates less earned work than planned at this status point. It does not forecast completion, identify the critical path or measure the cost incurred to do that work.

Questions you might have

Does a variance of −€20,000 mean a particular number of days late?

No. Translating earned-value variance into time requires the baseline schedule and the distribution of planned work.

Choosing the right inputs

Earned value (EV)
Use budgeted value of completed work under the project baseline. Do not substitute actual expenditure, billing or cash collected.
Planned value (PV)
Use budgeted value scheduled by the same date. Scope, baseline and progress-measurement policy must match those used for earned value.

Common mistakes to avoid

  • Do not use actual cost as earned value; spending is not the same as completing budgeted work.
  • Do not label a monetary schedule variance as a calendar delay or a percentage cost overrun.

Assumptions to check

  • Use amounts in one currency and one reporting period. Results are labelled EUR; the arithmetic also works for another consistent currency.
  • EV and PV must share the same status date, budget baseline and measurement policy.

Sources and method

Read our calculation and testing approach.