Percentage Increase Calculator

Formula

Increased value = Original value × (1 + Increase ÷ 100)

Worked example

With Original value: 100, Increase: 20 %, increased value is 120.

Calculation method

The rule is Increased value = Original value × (1 + Increase ÷ 100).

Increasing by p% means multiplying the original value by 1 + p/100. The answer is the new total, not the size of the increase alone.

For this percentage increase example, changing original value from 100 to 101 while keeping the other inputs fixed changes increased value from 120 to 121.2.

Reading increased value

The result represents a proportion or an adjusted value. A percent change is relative to the original value, while a percentage-point difference is the arithmetic difference between two percentages. In the worked values on this page, original value 100, increase 20 % produce increased value 120.

Practical use

Use percentages to compare prices, scores, growth, discounts, and rates when the quantities share a meaningful reference base. The specific task here is to find increased value from original value, increase.

Limits and common mistakes

A change from 20% to 25% is 5 percentage points but a 25% relative increase. Mixing the two descriptions is a common source of error. Verify original value before interpreting increased value; a value measured on another basis would answer a different question.

Why the relationship works

A percent is a ratio expressed per hundred. Before calculating, identify the reference amount: the number of which a percentage is taken, the whole used to find a share, or the original amount used to measure change. Switching that reference changes the question even when the same two numbers appear. The percentage increase rule uses original value, increase (%) in Increased value = Original value × (1 + Increase ÷ 100); read each symbol as the field named on this page.

Interpreting another set of values

For percentage increase, the fields labeled original value, increase (%) are the known quantities. The calculator solves for increased value using Increased value = Original value × (1 + Increase ÷ 100). Say which quantity is the percentage base and whether the answer is a rate, a change, or a new total. Those are different outputs even when they use the same starting figures. When comparing two calculations, keep their units and input definitions identical.

For a second percentage increase check, keep the other default inputs fixed and change original value from 100 to 102. Increased value changes from 120 to 122.4. This is a comparison of two particular cases. Repeat it near the values relevant to your task; do not assume that every formula changes at a constant rate.

Checks and limits

Keep the percentage and percentage-point concepts separate. A 20% increase followed by a 20% decrease does not return to the starting value, because the second change uses a different base. Check whether you need the adjusted total, the size of the adjustment, or the rate itself before using the result. The reported increased value is 120 in the worked example. Keep its stated unit or counting convention when checking it against another calculation.