Excel Percentage Calculator
Understanding and calculating percentages is a fundamental skill in Excel, crucial for financial analysis, sales reporting, performance tracking, and more. This tool helps you perform two of the most common percentage calculations you'd typically do in Excel: finding a percentage of a total and calculating percentage change.
1. Calculate Percentage of a Total
This calculation determines what proportion one number (the part) represents of another number (the total), expressed as a percentage. In Excel, this is often used to see what percentage of total sales a specific product contributes, or what percentage of a budget a particular expense consumes.
The formula is: (Part Value / Total Value) * 100
2. Calculate Percentage Change
Percentage change measures the degree of change over time. It's widely used to compare sales figures month-over-month, year-over-year, or to track growth or decline in any metric. In Excel, you'd use this to see how much a value has increased or decreased relative to its starting point.
The formula is: ((New Value - Old Value) / Old Value) * 100
How to Perform These Calculations in Excel
Percentage of a Total in Excel:
Let's say you have "Sales for Product A" in cell A2 (e.g., 15000) and "Total Company Sales" in cell B2 (e.g., 100000).
To find what percentage Product A's sales are of the total, you would enter the following formula in an empty cell (e.g., C2):
= (A2 / B2) * 100Or, more commonly, you would enter = A2 / B2 and then format cell C2 as a "Percentage" using the Number group on the Home tab. Excel will automatically multiply by 100 and add the '%' sign.
Example: If Product A Sales = 15,000 and Total Sales = 100,000, then (15,000 / 100,000) * 100 = 15%.
Percentage Change in Excel:
Suppose you have "Previous Month's Sales" in cell A2 (e.g., 80000) and "Current Month's Sales" in cell B2 (e.g., 92000).
To calculate the percentage change, you would use the following formula in an empty cell (e.g., C2):
= ((B2 - A2) / A2) * 100Again, you could also enter = (B2 - A2) / A2 and then format cell C2 as a "Percentage".
Example: If Old Value = 80,000 and New Value = 92,000, then ((92,000 – 80,000) / 80,000) * 100 = (12,000 / 80,000) * 100 = 0.15 * 100 = 15% increase.
If Old Value = 92,000 and New Value = 80,000, then ((80,000 – 92,000) / 92,000) * 100 = (-12,000 / 92,000) * 100 ≈ -13.04% decrease.
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