The basic method for any calculator

To calculate a power (also called an exponent) on most calculators, you enter the base number, press the power button, then enter the exponent. The power button is usually labeled ^, x^y, y^x, or ** depending on your calculator model. For example, to calculate 2 to the power of 3 (which equals 8), you would press: 2, then the power button, then 3, then equals.

The order matters. The first number you enter is the base — the number being multiplied. The second number is the exponent — how many times to multiply it by itself. If you reverse them, you will get a completely different answer.

Some older or simpler calculators do not have a dedicated power button. If yours does not, you can multiply the number by itself the required number of times instead. For 2 to the power of 3, you would press 2 × 2 × 2 = to get 8.

Key Takeaways

  • The power button on most calculators is labeled ^, x^y, y^x, or **, and the order is always base number first, then exponent.
  • Entering 2, power button, 3 calculates 2 to the power of 3, which equals 8.
  • If your calculator has no power button, you can multiply the base number by itself as many times as the exponent requires.
  • Negative exponents (like 2 to the power of -3) produce fractions, and most calculators handle these automatically.
  • Scientific calculators and phone calculator apps both have power functions, though the button location varies by device.

Finding the power button on your specific calculator

The location and label of the power button depends on what kind of calculator you have. On a scientific calculator (the kind with many buttons), look for a button labeled ^ or x^y. These are usually in the upper rows near other math operation buttons. On some models, it might say y^x instead, which works the same way — you still enter the base first.

On a graphing calculator like a TI-84, the power button is usually ^ and appears in the upper left area of the button grid. On a basic four-function calculator (the kind with just +, −, ×, ÷), there usually is no power button at all, so you will need to use the multiplication method instead.

On a phone or computer calculator app, the power button is often hidden in a second menu. On iPhone, open the Calculator app, turn your phone sideways to landscape mode, and you will see a ^ button appear. On Android, open the calculator, tap the menu icon (three horizontal lines or three dots), and select "Scientific" to reveal the power button. On Windows, open Calculator, click the menu icon, and choose "Scientific" mode.

Working with negative exponents

A negative exponent means you are dividing instead of multiplying. For example, 2 to the power of -3 equals 1 divided by (2 × 2 × 2), which is 0.125. Most calculators handle this automatically — you just enter the negative sign before the exponent number.

To calculate 2 to the power of -3, press: 2, power button, then −3 (or −, then 3 depending on your calculator), then equals. The calculator will return 0.125. Do not enter the negative sign before the base number unless you actually want to calculate a negative number to a power, which is a different operation.

Calculating large powers without a power button

If your calculator has no power button and the exponent is large, repeated multiplication becomes tedious. For 2 to the power of 10, you would need to press 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 =, which is error-prone and slow.

In this case, the easiest solution is to use your phone's calculator app instead, since all phone calculators have a power function once you switch to scientific mode. If you must use a basic calculator, break the exponent into smaller chunks. For 2 to the power of 10, you could calculate 2 to the power of 5 first (2 × 2 × 2 × 2 × 2 = 32), then multiply that result by itself (32 × 32 = 1024). This reduces the number of button presses and the chance of making a mistake.

Common mistakes and how to avoid them

The most common error is entering the numbers in the wrong order. Remember: base first, exponent second. If you press 3, power button, 2, you get 9 (3 squared). If you press 2, power button, 3, you get 8 (2 cubed). These are not the same, so double-check before you press equals.

Another frequent mistake is forgetting to press the power button at all and just multiplying instead. If you need 5 to the power of 4 and you press 5 × 4 =, you get 20, which is wrong. The correct answer is 625. Always look for and press the dedicated power button.

If your calculator shows an error message or a very large number that does not make sense, you may have entered a power that is too large for the calculator to handle. Most basic calculators cannot compute numbers larger than about 10 to the power of 99. If this happens, try a different calculator or break the problem into smaller steps.

Using the power function on different devices

A physical scientific calculator is the most straightforward. Find the ^ or x^y button, enter base, press it, enter exponent, press equals. No extra steps needed.

On a computer, open the built-in calculator app. On Windows 10 or 11, search for "Calculator" in the Start menu, open it, click the menu icon (three horizontal lines), and select "Scientific". On Mac, open Spotlight (Command + Space), type "Calculator", and press Enter. The Mac calculator does not have a dedicated power button in standard view, but you can use the menu: click "View" and select "Scientific", then look for the ^ button.

On a smartphone, the process is similar. iPhone: open Calculator, rotate to landscape. Android: open Calculator, tap the menu, select "Scientific". Once in scientific mode, the ^ button will be visible and works the same way as a physical calculator.

Frequently Asked Questions

What is the difference between x^y and y^x buttons?

They do the same thing — the letters just indicate which number goes where. x^y means "x to the power of y", so you enter x first. y^x means "y to the power of x", so you still enter the base first and the exponent second. The button name does not change the order you press the numbers.

Can I calculate a power of a decimal number?

Yes. Enter the decimal number as your base, press the power button, enter the exponent, and press equals. For example, 1.5 to the power of 2 equals 2.25. Decimals work exactly the same way as whole numbers.

What does it mean if my calculator shows "E" or "E+" in the answer?

This is scientific notation, used when the answer is very large or very small. For example, 2 to the power of 100 might display as 1.27E+30, which means 1.27 followed by 30 zeros. The calculator is not broken — it is just displaying the number in a more compact form because the full number would not fit on the screen.

Why does 0 to the power of 0 give me an error?

Mathematicians debate what 0 to the power of 0 should equal, and different calculators handle it differently. Some return 1, some return 0, and some show an error. For practical purposes, avoid this calculation — it does not come up in most real-world problems.

Can I use the power button to calculate square roots?

Yes, but you need to use a fractional exponent. A square root is the same as raising a number to the power of 0.5. For example, to find the square root of 16, you would enter 16, power button, 0.5, equals, and get 4. A cube root uses 0.333 (or 1/3) as the exponent.