The basic formula for percentage increase

To calculate percentage increase in Excel, subtract the original value from the new value, divide by the original value, then multiply by 100. The formula is: =((New Value - Original Value) / Original Value) * 100

If your original value is in cell A1 and your new value is in cell B1, you would write =((B1-A1)/A1)*100 in an empty cell. Excel will return the percentage increase as a number — for example, 25 for a 25% increase.

You can also format the result as a percentage instead of multiplying by 100. Use =((B1-A1)/A1) and then format the cell as a percentage. Both methods give the same result; the second just looks cleaner if you are building a spreadsheet others will read.

Key Takeaways

  • The percentage increase formula divides the change by the original amount: ((New - Original) / Original) * 100.
  • You can multiply by 100 in the formula or format the cell as a percentage — both produce the same result.
  • Percentage decrease uses the same formula structure; a negative result means the value went down.
  • Copy the formula down a column to calculate percentage change for multiple rows at once.
  • Always divide by the original value, not the new value, or your calculation will be wrong.

Setting up your data in columns

Organize your data so the original values are in one column and the new values are in another. For example, put original prices in column A and new prices in column B. Leave column C empty for your percentage increase calculations.

Click on cell C1 and type the formula =((B1-A1)/A1)*100. Press Enter. Excel calculates the percentage increase for that row and displays the result in C1.

If you have multiple rows of data, you do not need to type the formula again for each row. Click on C1, then drag the small square at the bottom-right corner of the cell down to the last row with data. Excel automatically adjusts the cell references (A2, B2 for row 2; A3, B3 for row 3, and so on) and fills in all the calculations at once.

Formatting the result as a percentage

If you use the formula =((B1-A1)/A1) without multiplying by 100, the result appears as a decimal — 0.25 instead of 25. To display it as a percentage, select the cell or cells with your results, then right-click and choose Format Cells.

In the Format Cells dialog, click the Number tab, then select Percentage from the Category list on the left. Set the decimal places to 0 if you want whole numbers (25%) or leave it at 2 for more precision (25.00%). Click OK.

Excel now displays your results as percentages. This method is cleaner than multiplying by 100 in the formula, especially if you are sharing the spreadsheet with others who expect to see percentage symbols.

Calculating percentage decrease

The same formula works for percentage decrease. If the new value is smaller than the original, the result will be negative. For example, if a price drops from $100 to $75, the formula =((75-100)/100)*100 returns -25, meaning a 25% decrease.

Some people prefer to rearrange the formula to show decreases as positive numbers: =((Original Value - New Value) / Original Value) * 100. This flips the subtraction order. Use whichever version matches how you want to present the data.

Avoiding common mistakes

The most frequent error is dividing by the new value instead of the original value. If you write =((B1-A1)/B1)*100, your answer will be wrong. Always divide by the starting point, not the ending point.

Another mistake is forgetting to lock the original value when copying the formula down. If your original values are in a single cell (for example, you are comparing all new values to one baseline), use an absolute reference: =((B1-$A$1)/$A$1)*100. The dollar signs tell Excel to keep A1 fixed when you copy the formula down, while B1 changes to B2, B3, and so on.

Check your first calculation by hand to make sure the formula is working correctly before copying it to many rows. A small error in the formula will repeat across your entire spreadsheet.

Using percentage increase in real scenarios

Sales teams use this formula to track month-over-month growth. If January sales were $50,000 and February sales were $62,500, the percentage increase is 25%. Marketing departments calculate how much traffic increased from one campaign to the next. HR departments track salary increases or headcount growth year to year.

You can also use it to compare your own numbers against industry benchmarks or competitor data. If your revenue grew 15% but the industry average is 20%, the formula shows you where you stand relative to others in your field.

Frequently Asked Questions

What if my original value is zero?

Excel will return a #DIV/0! error because you cannot divide by zero. If you have zero as a starting point, percentage increase is not mathematically meaningful — you cannot compare something that did not exist. Consider whether you need a different calculation or whether that row of data should be excluded.

Can I use this formula for negative numbers?

Yes, but the result can be confusing. If you start with -10 and end with -5, the formula shows a 50% increase (the value got closer to zero). The math is correct, but the meaning depends on your context. Always think about whether the result makes sense for what you are measuring.

How do I show the result with a plus or minus sign?

Use custom formatting. Right-click the cell, choose Format Cells, click the Number tab, select Custom, and enter the format code +0.00%;-0.00%. This displays positive increases with a plus sign and decreases with a minus sign. Adjust the zeros for more or fewer decimal places.

What is the difference between percentage increase and percentage point increase?

Percentage increase is what the formula calculates — the relative change from the original value. A percentage point increase is the absolute difference. If something goes from 20% to 25%, that is a 5 percentage point increase but a 25% increase in the original value (5 divided by 20 equals 0.25).