How to Square a Number in Excel

What this does

POWER raises a number to an exponent and is exactly equivalent to the ^ operator, so which you use is a readability decision rather than a functional one. Its real everyday value is fractional exponents, which produce roots: raising to 1/3 gives a cube root, and raising a growth ratio to 1/n is the core of every compound-growth calculation. A CAGR is literally =POWER(end/start, 1/years)-1. Negative exponents give reciprocals. A negative base with a fractional exponent has no real answer and returns #NUM!. Most people learn this as a sequence of clicks and forget it by next week; learning it as a pattern instead is what lets you apply it to the next, slightly different version of the problem without starting from scratch. That is the difference this page is trying to make. For “square a number 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

Compound annual growth from 120,000 to 195,000 over 4 years: =POWER(195000/120000, 1/4)-1 returns about 0.1281, or 12.81 %. A cube root of 27 is =POWER(27, 1/3), which returns 3. Doubling capacity ten times over: =POWER(2, 10) returns 1024. POWER is the backbone of every compound-growth and rate calculation, because the fractional exponent is what converts a total change into a per-period one. 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

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. 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. The short version of “square a number in excel”: the answer is at the top of this page, the tool proves it on your own numbers, and the sections above explain why it holds so the next variation does not stump you. Excel rewards people who reference cells instead of typing values and who keep inputs separate from formulas, because that is what makes a result you can audit months later. Build it once, deliberately, with the live tool as a check, and you convert a one-off lookup into a reusable skill — which is the whole point of learning the why and not just the what.

Common mistakes

• Writing 1/4 without brackets inside a larger expression, where operator precedence changes the meaning — wrap the exponent when in doubt.
• Taking a fractional power of a negative base, which returns #NUM! because no real root exists.
• Forgetting the -1 in a growth-rate formula, which reports the growth factor (1.128) rather than the rate (12.8 %).

Frequently asked questions