Math calculators

Percentage, ratio, fraction, and core math calculators.

• Percentage Calculator Calculate any percentage of a number. Enter the percent and the value, get the result instantly. Plus mental tricks to do percentages in your head.
• Percentage Change Calculator Calculate the percentage change between two numbers. Enter the original and new values to see the absolute change and percent change, signed for direction.
• Percentage Decrease Calculator Calculate the new value after a percentage decrease. Enter the original number and the percent to subtract for the result and the size of the drop.
• Percentage Increase Calculator Calculate the new value after a percentage increase. Enter the original number and the percent increase to see the result and the dollar (or unit) change.
• Percentage Of Calculator Calculate what X percent of Y is. Enter the percent and the value to see the result, plus the value plus that percent and the value minus that percent.
• Ratio Calculator Solve a ratio for the missing term. Enter three of A, B, C, D in the proportion A:B = C:D and the calculator returns the fourth using cross-multiplication.