Percent change, percent of, and what percent
Percentage change is the difference between two values divided by the starting value, times 100. It is always measured against the starting point, which is why a 10% cut followed by a 10% raise does not get back to the original figure. "Percent of" multiplies a number by the percentage as a decimal, and "what percent" divides one number by another.
Worked example (pre-filled). From $55,000 to $57,200 is a change of 2,200, which is 4.00%: a 4% raise, in other words. The multiplier is 1.04×. In the second box, 15% of an $84.50 restaurant bill is 12.68.
The reverse direction is the one that trips people up. $57,200 back to $55,000 is a fall of $2,200 on a larger base, so it is a 3.85% decrease, not 4%. The same asymmetry shows up in prices, pay cuts and investment losses: a 50% loss needs a 100% gain to recover. For pay specifically, the raise calculator adds the per-paycheck and after-tax view, and the tip calculator handles the restaurant case with tax and splitting.
Formula and assumptions
percent of = percent ÷ 100 × number
what percent = from ÷ to × 100
- A "from" value of zero has no defined percentage change; the tool shows a dash.
- Negative numbers are allowed; the change is measured against the absolute value of the start.
Frequently asked questions
How do I calculate percentage change?
Subtract the old value from the new value, divide by the old value, and multiply by 100. From 50 to 60 is (60 − 50) ÷ 50 × 100 = 20%.
What is 15% of 84.50?
$12.68. Multiply 84.50 by 0.15.
Why is a 20% increase not undone by a 20% decrease?
Because the decrease is taken from the larger number. 100 → 120 → 96. To get back from 120 to 100 you need a 16.67% decrease.
What is the difference between percentage points and percent?
Going from 4% to 5% is a rise of 1 percentage point but a 25% increase in the rate itself.
Related calculators
- All loans & money calculators
- Pay raise calculator: New pay from a percentage or dollar raise, per year, per paycheck and after Georgia taxes
- Tip calculator: Tip, tax and total per person, with a 15% to 25% table
- Salary to hourly calculator: Convert a salary to an hourly rate and back, with weekly, biweekly and monthly pay
- Georgia paycheck calculator: take-home pay after federal, FICA and Georgia tax
- Georgia income tax rate 2026 (a flat 4.99%)
Sources
This calculator gives general estimates from the figures you enter. It is not tax, legal, payroll or financial advice. See our disclaimer.