See the percentage, not just the number.

Work through three common percentage questions in one focused workspace.

Percentage questions

Percentage

Reference number

Part

Ratio reference

Starting value

New value

Result

20% of 80

16 as a % of 80

20%

80 → 100

25%

increase

Processed locally — inputs and results stay in this browser tab. Copy and download actions run only when you choose them.

Calculate any percentage of a number with a visible formula.

Open

Calculate percentage increase or decrease from an original value to a new value.

Open

Worked explanations for percent-of, ratio, percent change, reverse percentages, and percentage points.

Open

How PercentDock processes numeric inputs locally.

Open

“Percent of,” “what percent,” and “percent change” use related but different denominators. Labeling the reference value prevents many mistakes.

PercentDock

Work out shares, changes, markups, and reverse percentages.

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