Percentage Calculator
Use this calculator to find out what percentage one number is of another. Simply enter the 'Part Value' and the 'Whole Value' into the fields below, and the calculator will instantly show you the percentage.
Understanding Percentages
A percentage is a way of expressing a number as a fraction of 100. It's often denoted using the percent sign (%). For example, 50% means 50 out of 100, or one-half. Percentages are widely used in everyday life to describe proportions, discounts, statistics, and changes over time.
The Formula
The basic formula to calculate what percentage a 'part' is of a 'whole' is:
(Part Value / Whole Value) * 100 = Percentage
When to Use This Calculation
- Test Scores: If you scored 85 out of 100 on a test, what's your percentage? (85 / 100) * 100 = 85%
- Discounts: A product originally costs $50, and you save $10. What percentage is the saving? (10 / 50) * 100 = 20%
- Proportions: In a group of 200 people, 40 are left-handed. What percentage are left-handed? (40 / 200) * 100 = 20%
- Ingredient Ratios: If a recipe calls for 150g of flour and 50g of sugar, what percentage of the dry ingredients is sugar? (50 / (150 + 50)) * 100 = 25%
Examples of Percentage Calculations
Let's walk through a few examples to solidify your understanding:
Example 1: Simple Score
You got 75 questions correct out of a total of 100 questions on an exam.
- Part Value: 75
- Whole Value: 100
- Calculation: (75 / 100) * 100 = 75%
Example 2: Discount Amount
A shirt costs $40, and you received a $10 discount.
- Part Value: 10 (the discount amount)
- Whole Value: 40 (the original price)
- Calculation: (10 / 40) * 100 = 25%
Example 3: Population Data
Out of 500 surveyed individuals, 120 prefer coffee over tea.
- Part Value: 120 (those who prefer coffee)
- Whole Value: 500 (total surveyed)
- Calculation: (120 / 500) * 100 = 24%
This calculator simplifies these common calculations, allowing you to quickly find the percentage of any number relative to another.
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font-size: 20px;
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text-align: center;
min-height: 30px;
display: flex;
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code {
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function calculatePercentage() {
var partValueInput = document.getElementById("partValue");
var wholeValueInput = document.getElementById("wholeValue");
var resultDiv = document.getElementById("percentageResult");
var partValue = parseFloat(partValueInput.value);
var wholeValue = parseFloat(wholeValueInput.value);
resultDiv.className = "result-container"; // Reset class for new calculation
if (isNaN(partValue) || isNaN(wholeValue)) {
resultDiv.innerHTML = "Please enter valid numbers for both fields.";
resultDiv.classList.add("error");
return;
}
if (wholeValue === 0) {
resultDiv.innerHTML = "The 'Whole Value' cannot be zero.";
resultDiv.classList.add("error");
return;
}
var percentage = (partValue / wholeValue) * 100;
resultDiv.innerHTML = "The percentage is:
" + percentage.toFixed(2) + "%";
}