Calculate percentage, percentage change, and percentage of total
A Percentage Calculator calculates percentage changes, percentage ratios, and percentage increases/decreases across 6 distinct math modules.
Divide the part by the whole and multiply by 100. For example, 25 out of 200 is 25 / 200 x 100 = 12.5%. In the tool, use the "X is what % of Y" card, enter 25 and 200, and it shows 12.5% instantly. Y cannot be zero.
Multiply the number by the percentage divided by 100. For example, 10% of 200 is 200 x 10 / 100 = 20. The "What is X% of Y" card does this as you type, and works with decimals such as 7.5% of 480, which is 36.
Subtract the old value from the new one, divide by the old value, then multiply by 100. Going from 150 to 180 gives (180 - 150) / 150 x 100 = 20% increase. A negative result is shown as a decrease. The starting value cannot be zero.
To add a percentage, multiply the number by (1 + percentage / 100); to subtract, multiply by (1 - percentage / 100). Adding 10% to 200 gives 220, and subtracting 10% gives 180. This is the quickest way to work out a price after a markup or a discount.
Because each percentage applies to a different base. Start with 100, add 50% to reach 150, then subtract 50% of 150 (which is 75) to end at 75, not 100. To undo a 50% rise you need a 33.3% fall. Percentage changes are not symmetrical.
A percentage point is the plain difference between two percentages, while percent change is relative to the starting value. If a rate rises from 4% to 5%, that is 1 percentage point, but a 25% increase (1 / 4 x 100). This calculator computes percent change between two values.
No. Toolskyt operates under a zero-server policy. All calculations, data formatting, and file exports are executed locally on your machine.
No, this tool is 100% free. There are no limits, sign-ups, subscriptions, or hidden charges required.