Free Percentage Calculator

Multiply the number by the percent, then divide by 100. For example, 15% of 80 is 15 × 80 ÷ 100 = 12. In this calculator, choose X% of Y, type 15 and 80, and click Calculate to get 12.

Divide the part by the whole and multiply by 100. If you scored 45 out of 50 on a test, 45 ÷ 50 × 100 = 90%. Choose X is what % of Y, type 45 as X and 50 as Y, then click Calculate.

Subtract the old value from the new one, divide by the old value and multiply by 100. Going from 50 to 75 is a 50% increase, and 80 to 60 is a 25% decrease, shown as -25%. Use the % change from X to Y mode.

Percentage points are the plain gap between two percentages, while percent change compares that gap with the starting value. A rate rising from 4% to 5% is up 1 percentage point but up 25%. This calculator gives percent change; subtract the two rates for points.

The answer would need a division by zero. That happens in X is what % of Y when Y is 0, and in % change when the From value is 0, since change from zero has no percent. Change that number and click Calculate again; no message explains it yet.

Whole-number answers show as they are. Other answers are rounded to four decimal places with trailing zeros removed, so 1 out of 3 shows 33.3333%. Results smaller than 0.00005 round to 0, and very large numbers can appear in e notation, such as 1e+24.

Multiply the number by the percent, divide by 100, then add that to the number. To add 15% to 80, 15% of 80 is 12, so the total is 92. There is no add-percent mode yet: choose X% of Y, then add the result yourself.

Yes. Both boxes take negative numbers and decimals, such as 12.5% of 200 (25) or -10% of 50 (-5). In % change mode the difference is divided by the absolute starting value, so going from -50 to -25 counts as a 50% increase.

Put the part in A1 and the whole in B1, type =A1/B1 in C1 and format C1 as a percentage. For the change from A1 to B1, use =(B1-A1)/ABS(A1). Those are the same formulas this calculator uses, before its four-decimal rounding.

The result only updates when you click Calculate. If you change a number afterwards, the old answer stays on screen until you click again. Switching modes clears the result, and the reset button clears both numbers but keeps your mode.

Yes. It's free, with no account and no limit on how many sums you run. Your numbers are worked out in your browser and never saved or sent. On the live site, Google Analytics counts page visits and ads load, but neither receives your numbers.