Percentage Calculator

Calculate percentages, increases, decreases, and percentage differences easily

What is X% of Y?

Percentage Of

X is what % of Y?

Value Of

Percentage Change

From To

The Ultimate Guide to Calculating Percentages

Percentage is one of the most widely used mathematical concepts in daily life, from calculating store discounts to analyzing complex financial trends. "Per cent" literally means "by the hundred", turning any proportion into a comparable base of 100.

Three Core Percentage Operations

1. Finding the Value (What is X% of Y?)

Useful for calculating sales tax, commissions, or tips. Convert the percentage to a decimal and multiply by the total.

Value = (Percentage / 100) × Total

Example: A 5% commission on a $2,000 sale is 0.05 × 2,000 = $100.

2. Finding the Proportion (X is what % of Y?)

Used to determine your score on a test or the percentage of a specific expense in your budget.

Percentage = (Part / Whole) × 100

Example: If you spent $300 out of a $1,200 budget on entertainment, that’s (300/1200) × 100 = 25%.

3. Percentage Change (Increase or Decrease)

Essential for tracking inflation, investment growth, or year-over-year performance.

Change % = ((New Value - Old Value) / Old Value) × 100

Frequently Asked Questions (FAQ)

Is x% of y the same as y% of x?

Yes! This is a useful mathematical trick. For instance, 8% of 50 is the same as 50% of 8. Both equal 4. This can make mental calculations much easier.

How to calculate percentage on a standard calculator?

Enter the number, hit multiply (×), enter the percentage, and then the % key. If your calculator lacks a % key, multiply by the percentage and divide the result by 100.

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