Calculating Variance Percentage
Subtract the reference value from the actual value, divide by the reference, and multiply by 100. Use the calculator for budget versus actual, forecast versus result, or original versus new values.
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A positive result is an increase from the reference; a negative result is a decrease. Whether that is favorable depends on what the numbers measure.
Variance percentage calculator
Enter a non-zero reference, budget, forecast, or original value and the actual or new value.
How to calculate variance percentage
- Choose the reference value. This is usually the budget, forecast, previous period, target, or original amount.
- Subtract reference from actual to get the variance amount.
- Divide the variance amount by the reference value.
- Multiply by 100, or display the decimal as a percentage.
Always name the reference. Reversing actual and reference changes both the denominator and the result, so “percentage variance between A and B” is incomplete unless the baseline is clear.
Variance percentage calculation examples
Revenue above forecast
Forecast revenue is 100 and actual revenue is 112. Variance amount = 112 − 100 = 12. Variance percentage = 12 ÷ 100 × 100 = 12%. Because this is revenue, the increase may be labeled favorable.
Cost above budget
Budgeted cost is 80 and actual cost is 92. The variance is +12, or +15%. It is still an increase mathematically, but in a cost context it is normally labeled unfavorable.
Variance percentage formula in Excel
Put the reference or budget value in A2 and the actual or new value in B2. Enter =(B2-A2)/A2 and format the result cell as Percentage. Do not also multiply by 100 when Percentage formatting is applied, or the display will be scaled twice.
=(B2-A2)/A2Variance percentage is not statistical variance
| Calculation | Inputs | Question answered |
|---|---|---|
| Variance percentage | Reference and actual values | How large is the change relative to the reference? |
| Statistical variance | A data set | How spread out are observations around their mean? |
| Coefficient of variation | Mean and standard deviation | How large is SD relative to the mean? |
For relative spread across a data set, use the coefficient of variation calculator. The higher-difficulty generic variance-calculator keywords in the screenshot refer to another statistical task and were not used as this page’s primary target.
Zero and negative reference values
A zero reference makes the percentage undefined because the formula would divide by zero. Report the absolute difference or choose an agreed non-zero reference instead. A negative reference can produce a mathematically consistent result whose direction is counterintuitive, so state the denominator convention explicitly.
Frequently asked questions
How do you calculate variance percentage?
Subtract reference from actual, divide by reference, and multiply by 100.
Is a positive variance favorable?
Not always. Higher revenue may be favorable, while higher cost may be unfavorable. The calculator lets you choose the context.
What if the reference is zero?
The percentage is undefined. Use the variance amount or another agreed reference.
Is this the same as percent difference?
No. Percent difference usually treats two values symmetrically by dividing their absolute difference by their average. Variance percentage uses one named reference as the denominator.
Related tool and formula reference
Use the coefficient of variation calculator for relative statistical spread, or calculate relative standard deviation in Excel.