How to Use

Mode 1 - X% of Y (Percent of a number)

Enter the percentage in field 1 and the number in field 2. Example: "What is 20% of 500?" → Enter 20 and 500 → Result: 100.

Mode 2 - Percentage Change

Enter the original value in field 1 and the new value in field 2. Returns the percentage increase or decrease. A negative result means a decrease.

Mode 3 - X is what % of Y

Enter the part in field 1 and the whole in field 2. Example: "50 is what percent of 200?" → Enter 50 and 200 → Result: 25%.

Formulas

X% of Y

Result = (Y × X) ÷ 100

Percentage Change

Change = ((New − Old) ÷ |Old|) × 100

What % is X of Y

Result = (X ÷ Y) × 100

Examples

Sale discount - 15% off $80

Mode: X% of Y | Enter: 15, 80

15% of 80 = 12.00 (you save $12)

Salary increase - from $50,000 to $57,500

Mode: % Change | Enter: 50000, 57500

Change = +15.00% increase

Test score - 42 correct out of 56 questions

Mode: X is what % of Y | Enter: 42, 56

42 is 75% of 56

FAQ

Use the % Change mode. Enter the original value in field 1 and the new value in field 2. A positive result means an increase, a negative result means a decrease.

Use the X is what % of Y mode. Enter the part (smaller number) in field 1 and the whole (larger number) in field 2. The result is the percentage.

Use the X% of Y mode. Enter the discount percentage in field 1 and the original price in field 2. The result is the discount amount. Subtract it from the original price to get the final price.