Percentage Increase, Change & Difference Calculator

A percentage increase is the shorthand every raise, price hike, and interest rate hides behind. The engine is one line: New Value = Old Value × (1 + r ÷ 100). Increase 25 by 5% and you get 26.25, because 25 × 1.05 = 26.25. Flip the direction toggle and the same math runs in reverse — 25 decreased by 5% is 23.75. The tool shows the worked line under the result, so you can always check the arithmetic by hand.

Percent change is the before-and-after question. Going from $50,000 to $52,000 is (52,000 − 50,000) ÷ 50,000 × 100 = +4%, a $2,000 difference. Direction matters more than people expect: traveling back down from $52,000 to $50,000 is only a −3.85% change, because the base changed. That asymmetry is why a 20% raise followed by a 20% pay cut leaves you worse off — 100 goes to 120, then 120 × 0.80 lands at 96, not back at 100.

Percentage difference is the symmetric cousin, used when neither number is 'first'. It divides the gap by the average of the two values: for 60 and 50 that is 10 ÷ 55 × 100 = 18.18%. Compare that with percent change — 50 up to 60 is +20%, while 60 down to 50 is −16.67% — and you can see why picking the right formula matters. Use difference for 'how far apart are these two?' and change for 'what happened between then and now?'

The fourth tab is the everyday workhorse: X% of Y. 15% of 2,000 is 0.15 × 2,000 = 300. The mental version: 10% of 2,000 is 200, half of that is 100, so 15% is 300. It also runs discounts in reverse — 15% off 2,000 leaves 1,700 — which is exactly the math every sale tag is quietly doing to you.

The money framing: a $1 an hour raise is $2,080 a year before taxes (2,080 hours in the standard work year), and $2 an hour is $4,160. A $25-an-hour worker bumped to $27 sees an 8% increase — $52,000 to $56,160. To know what any raise is worth after federal, state, and FICA taxes, run the new salary through the paycheck calculator; that is the number your budget actually feels.