If your starting value is in cell A2 and your ending value is in cell B2, the percentage change formula in Excel is:
=(B2-A2)/A2
This gives a decimal (like 0.15), not a percentage sign. To display it correctly, select the cell, then apply Format > Cells > Percentage (or press Ctrl+Shift+%), which turns 0.15 into 15%.
Copying the formula down a column
To apply the same formula to multiple rows, drag the fill handle down after entering the formula in the first row, or copy and paste it. Excel automatically adjusts A2/B2 to A3/B3, A4/B4, and so on for each row.
Handling a zero or negative starting value
If A2 can be zero, the formula above returns a #DIV/0! error. Wrap it in IFERROR to handle this gracefully:
=IFERROR((B2-A2)/A2,"N/A")
If the starting value can be negative, use ABS() around A2 so the result stays meaningful (matching the same approach used in our negative numbers calculator):
=(B2-A2)/ABS(A2)
Comparing to a fixed starting value
If every row should be compared to the same starting value (say, in cell $A$1 instead of a value that changes per row), lock the reference with dollar signs so it doesn't shift when copied down:
=(B2-$A$1)/$A$1
Frequently asked questions
Why is my result showing as a decimal instead of a percentage?
The formula itself always returns a decimal; you need to apply percentage number formatting to the cell separately, as described above.
How do I show a plus or minus sign in front of the percentage?
Use a custom number format like +0%;-0% in the Format Cells dialog.
Can I calculate percentage change between two entire columns at once?
Yes — write the formula once in the first row (e.g., C2) and copy it down the rest of column C; each row will calculate independently.
Want to check a single calculation without opening Excel? Use the percentage change calculator.