Percentage Increase Calculator

Percentage increase calculator for comparing an original value to a new value

A percentage increase tells you how much a value grew relative to where it started. People use percent increase for price changes, salary adjustments, budget changes, sales growth, population growth, weight change, and almost anything where you have an “old” value and a “new” value. This calculator takes two numbers and shows both the change amount and the percentage change, so you do not have to do the math manually.

To use the calculator, enter the original value (the starting number) and the new value (the ending number). The result includes the difference between the two values and the percentage change. If the new value is higher than the original value, the percentage will be positive and the label will show an increase. If the new value is lower, the percentage will be negative and the label will show a decrease. That makes it useful even if you are comparing values that went down, without needing a separate percent decrease tool.

Understanding the outputs is straightforward. The change amount is simply new minus original. The percentage change is the change amount divided by the original value, multiplied by 100. That “relative to the original value” part is the key. A change of 50 might be huge if you started at 100, but minor if you started at 10,000. Percent change lets you compare changes across different scales.

This calculator is useful for real-world situations where you need a quick, consistent answer. For example, if a product price moved from 799 to 899, the calculator shows both the absolute change (100) and the percentage change, which is easier to compare across multiple products. If you are tracking a KPI like monthly revenue, percent increase gives you a fast sense of growth rate rather than just raw currency movement. For personal planning, it is also helpful when checking whether a salary increase keeps up with inflation, or how much a monthly expense grew over time.

If you need to apply a percentage increase to a starting number (for example, “increase 1,000 by 15%”), this calculator can still help if you enter the original value and the calculated new value. In many cases, people mix up percentage points and percent increase. This tool avoids that confusion by always anchoring the calculation to the original value and showing the full relationship between the two numbers.

Assumptions and how to use this calculator

• The original value must be greater than 0 to compute a meaningful percentage change.
• The new value can be any number, including 0, but the percentage is always measured relative to the original value.
• Results are shown with two decimals for consistency and easy comparison across scenarios.
• If the new value is lower than the original value, the result will display a negative percentage (a decrease).
• For currency-style use cases, this tool does not add currency symbols, but you can interpret the numbers as money if that fits your scenario.

Common questions

What is the formula for percentage increase?

The formula is: percentage change = ((new value − original value) ÷ original value) × 100. If the new value is larger, the result is positive (increase). If it is smaller, the result is negative (decrease).

Why can’t I calculate a percentage change from an original value of 0?

Percentage change is defined relative to the starting point. Dividing by 0 is not valid in normal arithmetic, so a percent increase from 0 is not a single defined number. In practical terms, any positive move from 0 is an “infinite” increase, which is why this calculator requires an original value greater than 0.

Is percentage increase the same as percentage points?

No. Percentage points describe the difference between two percentages (for example, from 10% to 12% is +2 percentage points). Percentage increase compares the size of a change relative to the original value. They are used for different kinds of comparisons.

How do I calculate percent increase for prices or salary?

Enter the old price or old salary as the original value, and the new price or new salary as the new value. The calculator will show the increase amount and the percentage change, which helps you compare different items or offers fairly.

What does a negative result mean?

A negative result means the new value is lower than the original value. The change amount will be negative, and the percentage change will also be negative. That is effectively a percentage decrease, displayed using the same consistent method.