Percentage Calculator

Find any percentage instantly — what is X% of Y, percent change between two numbers, and tip amounts. Real-time results, history, and clipboard copy. 100% free, nothing leaves your browser.

What is ___% of ___?
% of = ?
Result
—
Formula Result = Number × (Percent / 100)
e.g. "What is 15% of 200?" → 200 × 0.15 = 30
___ is what % of ___?
is what % of ?
Result
—
Formula Percent = (Part / Whole) × 100
e.g. "30 is what % of 200?" → (30 / 200) × 100 = 15%
Percent change from ___ to ___
→
Percent Change
—
Formula % Change = ((New − Old) / |Old|) × 100
Positive = increase  |  Negative = decrease
Calculate tip for your bill
people
15%
$0.00
Total: $0.00
18%
$0.00
Total: $0.00
20%
$0.00
Total: $0.00
25%
$0.00
Total: $0.00

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For informational and educational purposes only. Results are computed using standard mathematical formulas. For tip calculations involving shared bills or tax-inclusive amounts, verify with the venue. For financial decisions based on percentage figures, consult a qualified professional.

Frequently Asked Questions

How do I calculate what percent of a number is?
To find X% of Y, multiply Y by X and divide by 100. For example, to find 15% of 200: 200 × 15 / 100 = 30. Equivalently, convert the percentage to a decimal (15% = 0.15) and multiply: 200 × 0.15 = 30.
How do I calculate what percentage one number is of another?
To find what percentage X is of Y, divide X by Y and multiply by 100. For example, 30 is what percent of 200? Answer: (30 / 200) × 100 = 15%. So 30 is 15% of 200.
How do I calculate percent change?
Percent change = ((New Value − Old Value) / Old Value) × 100. If the result is positive it's an increase; if negative, a decrease. For example, from 100 to 125: ((125 − 100) / 100) × 100 = 25% increase.
How do I calculate a tip?
To calculate a tip, multiply the bill amount by the tip percentage. For a $50 bill with a 20% tip: $50 × 0.20 = $10 tip, so the total is $60. The standard tipping range in the US is 15–20% for restaurants, with 18–20% being most common.
What is the percentage formula?
There are three core percentage formulas: (1) Part = Percent × Whole / 100, e.g., 15% of 200 = 30. (2) Percent = Part / Whole × 100, e.g., 30/200 × 100 = 15%. (3) Percent Change = (New − Old) / Old × 100, e.g., (150 − 100) / 100 × 100 = 50% increase.
How do I calculate a percentage discount?
To find the discounted price: Final Price = Original Price × (1 − Discount% / 100). For a $80 item with 25% off: $80 × 0.75 = $60. The discount amount is $80 − $60 = $20. Use the "What is X% of Y?" mode to find the discount amount directly.

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