How do I calculate a percentage of a number?

To find X% of Y, multiply Y by X and divide by 100. Or equivalently, multiply Y by X expressed as a decimal: Y × (X ÷ 100). Examples: 15% of 200 = 200 × 0.15 = 30. 8.875% of $120 = 120 × 0.08875 = $10.65. 0.5% of 50,000 = 50,000 × 0.005 = 250. A quick mental shortcut: 10% of any number is just the number divided by 10. Then 5% is half of 10%, 20% is double 10%, and 15% is 10% + 5%.

How do I calculate a restaurant tip?

To calculate a 20% tip: move the decimal point one place left to get 10%, then double it. On a $45 bill: 10% = $4.50, double = $9.00 tip. For 15%: find 10% ($4.50) and add half ($2.25) to get $6.75. For 18%: find 10% ($4.50), find 8% ($3.60), add them ($8.10). Or simply use this calculator — enter the bill amount as Y and the tip percentage as X. The table below the calculator shows every common tip percentage for your bill amount simultaneously, so you can choose your tip level at a glance.

How do I calculate a percentage discount?

To find the discounted price after a percentage off: (1) Find the discount amount: multiply the original price by the discount percentage ÷ 100. (2) Subtract from the original price. Example: 25% off $120: discount = $120 × 0.25 = $30. Discounted price = $120 − $30 = $90. Shortcut: multiply by (1 − discount%/100). For 25% off: $120 × 0.75 = $90. Or use Mode 1 of this calculator to find the discount amount, then subtract it from the original price.

What is the difference between percentage and percentage points?

Percentage and percentage points are different units that are commonly confused. A percentage is a number expressed as a fraction of 100. A percentage point is the arithmetic difference between two percentages. Example: if an interest rate rises from 3% to 5%, it increased by 2 percentage points — but it increased by 66.7% as a percentage change (2/3 × 100). If a test score improves from 60% to 75%, the improvement is 15 percentage points, or a 25% increase in score. In everyday conversation people often say 'percent' when they mean 'percentage points' — the context usually makes it clear, but in finance and statistics the distinction is precise and important.

How do I find what percentage one number is of another?

Divide the first number by the second, then multiply by 100. Formula: (X ÷ Y) × 100. Examples: 30 is what % of 200? → (30 ÷ 200) × 100 = 15%. 45 is what % of 60? → (45 ÷ 60) × 100 = 75%. $17.50 is what % of $70? → (17.5 ÷ 70) × 100 = 25%. This is useful for finding what percentage of a budget has been spent, what percentage of students passed an exam, or what portion of a recipe has been used. Use Mode 2 of this calculator — 'X is what % of Y?' — for instant results.

What is X% of Y? — Percentage Calculator

This percentage calculator solves the three most common percentage questions in one place. Mode 1: What is X% of Y? — enter the percentage and the base number, get the result instantly. Mode 2: X is what percentage of Y? — enter both numbers, find what percentage one is of the other. Mode 3: X% of w...

PERCENTAGE CALCULATOR

I want to find…

Percentage (X)

Number (Y)

What is 15% of 200?

15% of 200 = 30

QUICK EXAMPLES

LIVE DIAGRAM

RESULT

15% of 200 = 30

15% OF 200

0200

QUICK REFERENCE — COMMON PERCENTAGES OF 200

10%20

20%40

25%50

50%100

75%150

100%200

PERCENTAGE

15%

BASE NUMBER

200

RESULT

REMAINDER

170

Live diagram · updates as you type

Created with❤️byeaglecalculator.com

COMMON PERCENTAGE AMOUNTS OF 200

PERCENTAGE REFERENCE TABLE — BASE: 200

PERCENTAGE	AMOUNT	COMMON USE	REMAINDER
5%	10	Minimum tip / small fee	190
10%	20	Round tip / 10% discount	180
15% ←	30	Standard restaurant tip	170
18%	36	Suggested tip (some receipts)	164
20%	40	Good tip / common discount	160
25%	50	Excellent tip / quarter off	150
30%	60	Generous tip / seasonal sale	140
50%	100	Half price / 50% off	100
75%	150	Three-quarters	50
100%	200	Full amount	0

HOW TO USE

1
Select the type of percentage problem you want to solve using the three mode buttons: 'What is X% of Y?', 'X is what % of Y?', or 'X% of what = Z?'.
2
Enter your two known values. For 'What is X% of Y?': enter the percentage (e.g. 15) and the number (e.g. 200). The answer appears instantly.
3
Use the quick example buttons to load common calculations — restaurant tips, sales tax, or discounts — and see how the calculator works before entering your own numbers.
4
The reference table below the calculator shows all common percentages of your number (5%, 10%, 15%, 20%, 25%, 50%, 100%) — your entered percentage is highlighted in blue.
5
The live diagram shows your percentage as a filled bar relative to the full number, so you can see visually how large or small the percentage is.

WORKED EXAMPLE

Example 1 (What is X% of Y?): What is 15% of 200? → 200 × 15 / 100 = 30. What is 8.875% of $120? → 120 × 8.875 / 100 = $10.65 sales tax. What is 20% of $85? → 85 × 0.20 = $17 tip. Example 2 (X is what % of Y?): 30 is what % of 200? → 30 / 200 × 100 = 15%. Example 3 (X% of what = Z?): 15% of what number = 30? → 30 / 0.15 = 200.

REFERENCE FORMULAS

FORMULA REFERENCE TABLE

NAME	FORMULA	DESCRIPTION
X% of Y	Result = Y × (X / 100)	Find the percentage amount — multiply base by percentage as decimal
X is what % of Y	Percentage = (X / Y) × 100	Find what percentage X is of Y
X% of ? = Z	Base = Z / (X / 100) = Z × 100 / X	Find the base number when you know the percentage and the result
Remainder	Remainder = Y − (Y × X / 100)	What is left after removing X% from Y (e.g. discounted price)
Percent change	Change % = (New − Old) / Old × 100	Percentage increase or decrease between two numbers

FREQUENTLY ASKED QUESTIONS

RELATED CALCULATORS

X is What Percent of Y Calculator

Calculate instantly →

Percentage Change Calculator

Calculate instantly →

Percentage Off Calculator

Calculate instantly →

Percentage Increase Calculator

Calculate instantly →

MORE PERCENTAGE CALCULATORS

Grade Calculator

Calculate instantly →

Percentage Increase Calculator

Calculate instantly →

X is What Percent of Y Calculator

Calculate instantly →

Percentage Markup Calculator

Calculate instantly →

Percentage Difference Calculator

Calculate instantly →

Percentage Margin Calculator

Calculate instantly →

Percentage Off Calculator

Calculate instantly →

Percentage Decrease Calculator

Calculate instantly →

Discount Calculator

Calculate instantly →

Percentage Change Calculator

Calculate instantly →

Tip Calculator

Calculate instantly →

What is 5% of 1000?

Calculate instantly →

What is 5% of 250?

Calculate instantly →

What is 5% of 25?

Calculate instantly →

What is 5% of 150?

Calculate instantly →

What is 5% of 500?

Calculate instantly →

What is 5% of 20?

Calculate instantly →

What is 5% of 200?

Calculate instantly →

What is 10% of 20?

Calculate instantly →

Was this calculator helpful?

Last updated: April 25, 2026 · Formula verified by EagleCalculator team · Eagle-eyed accuracy for every calculation.