Percentage Change Calculator
Enter where a value started and where it ended; get the signed percent change instantly — +50% from 50 to 75, −33.33% back. Exact math, shareable results.
Enter your values to see instant results:
Keyboard shortcuts
| Tab / Shift+Tab | Next / previous field |
| ↑ / ↓ | Step a value by 1 (Shift: 10, Alt: 0.1) |
| Enter | Copy the focused row's result |
| [ / ] | Fewer / more decimal places |
| Esc | Clear the field |
What percentage change measures
Percentage change answers one question: relative to where it started, how far did it
move? The formula is (new − old) ÷ old × 100, and the division by the old
value is the entire point — a $25 price move is a shrug on a $500 phone (+5%) and a scandal
on a $50 one (+50%).
The direction lives in the sign: positive is growth, negative is decline. And because the base is the starting value, symmetric-looking moves aren't symmetric — up 50% then down 50% lands below where you began. That asymmetry isn't a quirk to memorize; it falls straight out of the formula, and it's why long sequences of changes should be multiplied as factors (1.5 × 0.5 = 0.75) rather than added as percents.
Change, difference, or points?
Three cousins get mixed up in headlines. Percentage change is directional and uses the old value as base — this page. Percentage difference is direction-free and uses the average of the two values — its own calculator. Percentage points are the absolute difference between two numbers that are already percentages — a poll going 40% → 45% moved 5 points but changed 12.5%. Choosing the wrong one doesn't just look sloppy; it changes the number, sometimes by an order of magnitude.
Percentage change FAQ
What is the percentage change formula?
(new − old) ÷ old × 100. From 50 to 75: (75 − 50) ÷ 50 × 100 = +50%. From 75 to 50: (50 − 75) ÷ 75 × 100 = −33.33%. The sign carries the direction; the base is always the value you started from.
Why is the change from 50 to 75 not the same as from 75 to 50?
Because the base changes. Both moves cover 25 units, but +25 measured against 50 is +50%, while −25 measured against 75 is −33.33%. Percentage change is a ratio to the starting point, not a distance. If you want a direction-free comparison, that's the percentage difference.
How does percentage change work with negative numbers?
This calculator divides by the absolute value of the start: (new − old) ÷ |old| × 100. That keeps the sign meaningful — a move from −50 to −25 shows as +50%, because the value genuinely moved up. Not every tool makes this choice; some return −50% there. When comparing outputs across tools, check how each treats negative bases.
What is the change from zero?
Undefined — there's no base to measure against, and no percentage can describe going from 0 to 10. Say it in absolute terms instead ("grew from zero to 10 users"). The calculator tells you this rather than inventing a number.
Is a change of 5 percentage points the same as a 5% change?
No. An interest rate going from 4% to 9% rose 5 percentage points, but as a percentage change it rose 125%. News copy mixes these constantly. When both numbers are themselves percentages, "points" is almost always the clearer unit — the distinction is unpacked in this article.