In Excel: use =(New-Old)/Old and format the result as a percentage.
Increase of 48 units
Need it as an auditable file?
Ships inside the linked template — formula-driven, unlocked, audit-ready.
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. The difference between a quick fix and a sheet you can trust is the extra minute you spend validating “add a percentage increase in excel”. Start on a copy or a tiny sample, keep the affected cells visible, and compare the result with the tool above before you touch the real workbook. 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. The point is a calculation you can defend to a CFO or an auditor, but the practical win is that someone else can open the file and understand what happened without asking you.
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. If there is any chance you will reuse this, drop it into a small template tab right now: a labelled input area on the left and the formula beside it, checked once against the tool above. Next time the same question comes up, the answer is a single paste away instead of a rebuild from memory.
In Google Sheets
Everything above works in Google Sheets too. Excel and Sheets share the formula syntax used here; only the surrounding menus are arranged differently. That portability is deliberate — learn it once and it follows you between the two tools and across Windows and Mac. Keep this page bookmarked for the next time the same question comes up. Better still, rebuild the example once in your own sheet — doing it yourself, with the tool above to check against, is what turns a copied formula into a technique you own. Here is the takeaway for “add a percentage increase in excel”: copy the answer if you are busy, but if you have a spare few minutes, rebuild the example in Excel yourself with the tool above open beside it. That single pass — type it, run it, watch the result move when you change an input — is what turns a formula you found into a technique you trust. Keep your inputs labelled and referenced, never hard-coded, and the same sheet stays correct and auditable as it grows. Done that way, you will not need to look this up again, and you will be the person others ask.
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
Increase vs difference — same thing?
Percentage increase/decrease keeps the sign and uses the old value as base. Percentage difference between two independent figures usually divides by their average instead.
How do I show it with a + or − sign?
Apply a custom number format like +0.0%;−0.0% so increases and decreases are visually signed without extra formulas.
Why is my percentage huge?
Almost always a missing percent format (a value of 0.4 shown as 40 instead of 40%) or dividing by a very small base value.
Other ways people ask this
On the way here you may have searched this as “how to add a percentage increase in excel” and “how to add percentage increase in excel” — it is all the same task, and this page is the single, complete answer to it.
Why do people search for this in so many different ways?
Because the same task has many names. “how to add a percentage increase in excel”, “how to add percentage increase in excel” all point at the one operation explained on this page, which is why they all lead here.