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Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →For a percentage of a total, divide the part by the whole in Excel, then format the result as a percentage: enter =part/whole. For example, =42/50 returns 0.84, which displays as 84.00% when formatted as a percentage. The formula calculates the value; formatting controls how Excel displays it.
Choose the formula that matches your question
Assume B2 contains the original amount, part, or base amount; C2 contains the total, new amount, or rate; and D2 is where you want the result. Use the row that matches what you need to find.
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| Task | Formula | How to read it |
|---|---|---|
| What share is one amount of a total? | =B2/C2 |
Divide the part by the whole, then format the result as a percentage. |
| What is the percentage change from an old value to a new one? | =(C2-B2)/B2 |
B2 is the original value and denominator. A positive result is an increase; a negative result is a decrease. |
| How much is a given percentage of an amount? | =B2*C2 |
B2 is the base amount; C2 is a rate such as 8.9% or 0.089. |
| What is the amount after an increase? | =B2*(1+C2) |
Add the rate to 1, which represents 100%, before multiplying. |
| What is the amount after a decrease? | =B2*(1-C2) |
Subtract the rate from 1 before multiplying. |
| What was the original amount before a discount? | =sale_price/(1-discount) |
Divide the sale price by the fraction of the original price that remained after discount. |
These are standard percentage formulas described in Microsoft Support’s percentage guide and number-formatting guidance. For rates, enter either a decimal such as 0.25 or a percent such as 25%; both represent 25% in Excel.
Calculate a part as a percentage of a total
Enter the part in one cell and the whole in another, then divide the part by the whole. If 42 answers are correct out of 50, use =42/50 or, with cell references, =B2/C2. The result is 0.84; percentage formatting displays it as 84.00%. Microsoft’s worked example uses these same values.
Calculate percentage change from an original value
Subtract the original value from the new value, then divide that difference by the original value: =(new-original)/original. With the assumed cells, the formula is =(C2-B2)/B2. The original value belongs in the denominator; dividing by the new value answers a different question.
Microsoft’s examples show a change from 2,342 to 2,500 calculated as =(2500-2342)/2342, or about 6.75%, and a change from 2,500 to 2,425 calculated as =(2425-2500)/2500, or -3.00%. A negative result indicates a decrease.
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Find a percentage amount, or adjust an amount by a rate
Find the percentage amount
Multiply the base amount by the rate. For 8.9% tax on 800, use =800*8.9% or =800*0.089; the result is 71.2. With a base in B2 and rate in C2, use =B2*C2.
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Increase or decrease the amount
For an increase, multiply by one plus the rate; for a decrease, multiply by one minus the rate. For example, applying a 25% increase to 113 gives =113*(1+0.25), or 141.25. Applying a 25% decrease gives =113*(1-0.25), or 84.75. In both formulas, 1 stands for 100%.
Recover the pre-discount price
If a sale price of 15 reflects a 25% discount, the sale price is 75% of the original. Divide by that remaining share: =15/(1-25%), or =15/0.75, which returns 20.
Format the result as a percentage
- Enter the formula in the result cell and press Enter.
- Select the result cell.
- On the Home tab, select Percent Style. Microsoft also documents
Ctrl+Shift+%as a shortcut. - Use the decimal-place controls if you want more or fewer displayed digits. Changing the displayed decimal places does not change the formula’s underlying result.
Excel stores percentage values as decimal fractions for calculations: 0.1 formatted as a percentage displays as 10%. Formatting a cell that already contains the whole number 10 instead displays 1000%. To show 10%, first calculate a fraction such as =10/100, then apply percentage formatting.
Copy a percentage formula down a column
Use cell references so each row calculates from its own inputs. For example, put =B2/C2 in D2, then copy or fill the formula down the result column. Excel adjusts ordinary relative references for each row, so the next row uses B3/C3. This follows Microsoft’s guidance on copying percentage formulas and using cell references.
Show percentages for grouped data
Use a PivotTable percentage view
For grouped data, a PivotTable can show a value as a percentage of the grand total, a column total, a row total, or a parent total. In the PivotTable’s value field settings, use Show Values As and select the comparison that matches the question. The available labels and options can vary by Excel edition and release. See Microsoft’s PivotTable value calculation guidance.
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Use PERCENTOF in Microsoft 365
In Excel for Microsoft 365, PERCENTOF(data_subset,data_all) calculates the subset’s share of the full dataset by summing each range and dividing the sums. Microsoft describes it as logically equivalent to =SUM(data_subset)/SUM(data_all). Consult the PERCENTOF function documentation for its syntax and availability.
Quick Recap
Avoid denominator and data-entry errors
- Use the original value for percentage change. The formula is
(new-original)/original, not a division by the new value. - Check whether a rate is a percent or a whole number. Use
25%or0.25for a 25% rate, not25. - Do not percentage-format a whole-number result by mistake. A stored
10displays as1000%; calculate the decimal fraction first if the intended result is 10%. - Handle a zero denominator deliberately. A zero total or original value makes ordinary division undefined in Excel. Decide what a zero denominator means for the workbook before choosing a fallback; there is no single percentage result that applies to every case.
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