Excel Percent Change Calculator: Formula & Examples

This Excel percent change calculator works out the percentage increase or decrease between two numbers. You enter the old value and the new value, and it returns the percent change, showing whether it is an increase or a decrease. The calculation uses the standard formula (new – old) / old × 100, which is the same one used in Excel’s own percent change calculations.

Formula

The percent change formula is:

Percent change = ((New value – Old value) / Old value) × 100

• Old value – the starting or previous amount (no units, just the number).
• New value – the current or later amount (same units as old value).
• Percent change – the result, expressed as a percentage. A positive result means an increase; a negative result means a decrease.

The absolute difference (New – Old) is also shown, which is useful when you need the raw change, not the percentage.

Worked Example

Using the default values: Old = 50, New = 60.

1. Subtract the old value from the new: 60 – 50 = 10.
2. Divide by the old value: 10 / 50 = 0.2.
3. Multiply by 100 to get the percentage: 0.2 × 100 = 20%.

The result is a 20% increase. The absolute difference is 10.

How to Use Percent Change in Excel

If you are working directly in Excel, the formula is straightforward. Suppose your old value is in cell A1 and the new value is in B1. In cell C1, enter:

=(B1-A1)/A1

Then format cell C1 as a percentage (Home tab → Percent Style). Excel will display the result as a percentage, e.g., 20%.

For a column of data, you can copy the formula down. Be careful with the first row if you have headers – start the formula in the row that has both values.

Common Mistakes and How to Avoid Them

• Dividing by the new value instead of the old. Always divide by the old (starting) value. Dividing by the new value gives a different number and is not the percent change.
• Forgetting to format as percentage. If you see 0.2 instead of 20%, it is just a formatting issue – change the cell format to Percentage.
• Using absolute references incorrectly. When copying the formula down, use relative references (A1, B1) unless you want to lock a specific cell. Use $A$1 if you always want to compare to the same old value.
• Negative old value. If the old value is negative, the formula still works mathematically, but the interpretation can be tricky. For example, from -10 to -5: ((-5 – (-10)) / -10) × 100 = -50%, which is actually an increase (less negative). Always think about what the numbers mean.

When to Use Percent Change vs. Percentage Points

Percent change is relative – it compares the change to the original value. Percentage points are absolute – they measure the difference between two percentages directly.

Example: If a rate goes from 10% to 12%, the percent change is (12-10)/10 × 100 = 20% increase. But the percentage point change is 2 percentage points. Both are correct but answer different questions. Use percent change when you want to express growth or decline relative to the starting point; use percentage points when you are comparing two percentages directly.

Limitations of the Percent Change Formula

• Old value of zero. If the old value is 0, the formula divides by zero and returns an error (#DIV/0!). In that case, percent change is undefined – you cannot express a change from zero as a percentage. You might instead report the absolute change.
• Small denominators. When the old value is very small, even tiny absolute changes produce huge percentage changes. For instance, going from 1 to 2 is a 100% increase, but that may not be meaningful in context.
• Not symmetric. A 50% increase followed by a 50% decrease does not bring you back to the original. Example: 100 → 150 (50% increase) → 75 (50% decrease). The formula is not reversible, so avoid assuming symmetry.

Alternatives to Percent Change

Depending on what you need, other measures might be more appropriate:

• Absolute difference – simply new – old. Useful when the scale is small or when percentage change is misleading.
• Log change – ln(new/old). Often used in finance and economics because it is symmetric and handles compounding better.
• Percentage point change – for comparing two percentages directly.
• Compound annual growth rate (CAGR) – for growth over multiple periods, to get an annualized rate.

Frequently Asked Questions

How do I calculate percent change in Excel without a formula?

You can use the built-in percentage format, but you still need to enter a formula. There is no one-click percent change button. Enter =(B1-A1)/A1 and format as percentage.

What if my old value is zero?

Excel will return a #DIV/0! error because you cannot divide by zero. Percent change is undefined from zero. Report the absolute change instead, or use a different measure like the absolute difference.

How do I calculate percent change for negative numbers?

The formula works, but the interpretation can be counterintuitive. For example, from -10 to -5: ((-5 – (-10)) / -10) × 100 = -50%. This actually means the value increased (became less negative). Always consider the context and whether a percentage change makes sense.

What is the difference between percent change and percent difference?

Percent change uses the old value as the denominator: (new – old)/old × 100. Percent difference (often used in comparisons) uses the average of the two values as the denominator: |new – old| / ((new+old)/2) × 100. They answer different questions.

Can I use percent change for negative percentage values?

Yes, but be careful. If you are comparing percentages themselves (e.g., a rate going from -5% to -3%), the percent change is ((-3 – (-5)) / -5) × 100 = -40%, which is actually an increase. Again, context matters.

How do I calculate percent change for multiple rows at once?

Enter the formula in the first data row, then double-click the fill handle (the small square at the bottom-right of the cell) to copy it down the column. Make sure your references are relative.

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in old | Old value | - | 50 | 0
in new | New value | - | 60 | 0
out change | Percent change | % | ((new - old) / old) * 100 | 2
out diff | Absolute difference | - | new - old | 2