Percentage Change Calculator in Excel

What this does

Percentage change tells you how much a value rose or fell relative to where it started, which is what makes a €20 move on €100 (20%) and a €20 move on €400 (5%) comparable. Subtracting old from new gives the absolute change; dividing by the old value rebases it to a rate. A positive result is an increase, a negative one a decrease. Keep the inputs visible and clearly labelled and the whole thing stays auditable — anyone who opens the file later, including you, can see at a glance exactly what feeds the result and change one assumption without hunting through the formula. For “percentage change calculator in excel”, the reliable version is a short checking loop, not just the first command that appears to work. Run it on a deliberately small range first, watch how the affected cells change, and only then apply the same setup to the full sheet. When a formula is involved, keep the inputs labelled beside it, reference cells instead of typing values, and apply number formatting only after the result checks out. That is what makes a calculation you can defend to a CFO or an auditor useful in real work: repeatable, auditable, and not dependent on memory or luck.

A worked example

A price goes from 120 to 168: =(168-120)/120 = 0.4, formatted as 40% — a 40% increase. If it instead fell to 90, =(90-120)/120 = −25%. The tool above colours increases green and decreases red and also shows the raw unit change, so you see both the rate and the absolute move. Percentage change is the language of every trend: month-on-month revenue, year-on-year growth, price moves, conversion shifts. It turns two raw numbers into a comparable story anyone can read at a glance. One habit worth forming early: name the cells that hold your inputs, so the formula reads in plain language instead of a string of cell addresses. A reviewer — or you in three months — can then follow the logic without decoding what B7 and D2 were supposed to mean, which is most of what makes a sheet maintainable.

In Google Sheets

Google Sheets handles this almost identically to Excel. The formula syntax above is the same, and the menu lives under a slightly different label rather than a ribbon tab. Use the platform toggle at the top of the page to switch every keyboard shortcut between Windows and Mac, and expect at most cosmetic differences in naming. The aim was to get you unstuck fast and leave you a little more capable than a copy-paste would. The answer is at the top, the tool proves it, and the detail above shows why it holds — so the next time a colleague asks, you can answer without reaching for search. Treat “percentage change calculator in excel” as a small building block rather than a chore. Once the inputs sit in their own cells and the formula reads from them, the same setup answers a dozen related questions with a tweak, and Excel keeps every dependent figure current as the data changes. The tool above is there so you can rehearse and verify before committing anything to a real workbook; the steps and worked example are there so the logic sticks. Get it right once and it stops costing you time — it starts saving it, every time the question comes back around.

Common mistakes

• Dividing by the new value instead of the old — the base must be the starting point.
• Leaving the result as a decimal (0.4) instead of formatting it as 40%.
• Averaging percentage changes across periods instead of compounding them.
• Dividing by zero when the original value is 0, which has no defined percentage change.

Frequently asked questions