What is a scientific calculator?

A scientific calculator is a calculator that goes beyond adding, subtracting, multiplying and dividing. It can work with powers and roots, logarithms, trigonometry, factorials, percentages and brackets, and it follows the correct order of operations when you type a whole expression. Students use it for algebra, geometry, physics and chemistry. Engineers, builders, programmers and anyone who needs a quick answer to a harder problem use it too.

The calculator above works like a physical scientific calculator, but it runs in your browser. There is nothing to download, no sign-up, and the numbers you type are never sent to our server. It works on a phone, a tablet or a computer, and you can use either the on-screen keys or your keyboard.

How to use the calculator

1. Type a calculation with the keys, for example 2 + 3 × 4. You will see the full expression on the display as you build it.
2. Press = (or the Enter key) to get the answer. The expression stays on the small line above the result.
3. To keep working with the result, press an operator such as + or × straight away. To start a new calculation, just press a number.
4. Use ⌫ to delete the last item and AC to clear everything.
5. Tap DEG to switch between degrees and radians for trigonometry. The current mode is shown in the top left corner of the display.

What the keys do

Key	What it does	Example
sin, cos, tan	Sine, cosine and tangent of an angle	sin(30) = 0.5 in degree mode
sin⁻¹, cos⁻¹, tan⁻¹	Inverse trig functions, which return an angle	sin⁻¹(0.5) = 30 in degree mode
x², x³, xʸ	Square, cube and any power	2 xʸ 10 = 1024
√x, ∛x	Square root and cube root	√(144) = 12
ln, log	Natural logarithm (base e) and common logarithm (base 10)	log(1000) = 3
n!	Factorial of a whole number	5! = 120
π, e	The constants pi and Euler's number	2 × π = 6.28318530718
EXP	Enter a number in scientific notation	10 EXP 3 means 10 × 10³ = 10000
%	Divides the number before it by 100	80 × 15% = 12
1/x, ±	Reciprocal and change of sign	5, then 1/x = 0.2
M+, M−, MR, MC	Add to, subtract from, recall and clear the memory	Store a total and use it later
Ans	Inserts the previous answer	Reuse a result in a new calculation

Order of operations

The calculator follows the standard order of operations, sometimes remembered as PEMDAS or BODMAS. It works out brackets first, then exponents and roots, then multiplication and division from left to right, and finally addition and subtraction from left to right. This means 2 + 3 × 4 gives 14, not 20, because the multiplication happens first. If you want the addition to happen first, use brackets: (2 + 3) × 4 gives 20.

Exponents are applied from the top down, so 4 xʸ 3 xʸ 2 means 4 to the power of (3 squared), which is 4 to the power of 9, or 262,144. A minus sign in front of a number is applied after the power, so −5² gives −25 while (−5)² gives 25. If you leave brackets open, the calculator closes them for you when you press equals.

Degrees or radians?

Angles can be measured in degrees or radians. A full circle is 360 degrees, which equals 2π radians (about 6.283). Most school problems and everyday uses, such as building or navigation, use degrees. Calculus, physics and programming often use radians. The calculator starts in degree mode. If you get an unexpected answer from a trig function, check the mode first, because sin(30) is 0.5 in degree mode but about −0.988 in radian mode.

Worked examples

• Height of a ramp. A ramp is 6 metres long and rises at 15 degrees. The height is 6 × sin(15) = 1.55 metres, rounded.
• Percentage. Find 15% of 80 by typing 80 × 15 % and pressing equals. The answer is 12.
• Compound growth. Money growing at 5% a year for 10 years multiplies by 1.05 xʸ 10, which is 1.62889. Our Compound Interest Calculator does the full job with deposits.
• Scientific notation. Type 3 EXP 8 to enter 3 × 10⁸, close to the speed of light in metres per second.
• Combinations. The number of ways to arrange 5 different books is 5! = 120.

Keyboard shortcuts

Click the calculator once, then type. The number keys, decimal point, + − * / ( ) ^ % and ! all work. Press Enter or = for the answer, Backspace to delete the last item and Escape to clear. Use * for multiplication and / for division, as on a computer keyboard.

Tips for accurate results

• Check brackets. Most wrong answers come from a missing bracket. Read the expression on the display before you press equals.
• Use the right mode. Look at DEG or RAD before any trig calculation.
• Keep full precision. Use Ans instead of retyping a rounded number from a previous step.
• Estimate first. A quick mental estimate will catch typing mistakes. For example, 29 × 31 should be close to 30 × 30 = 900.
• Know the limits. The calculator shows about 12 significant digits. Factorials work up to 170!, and dividing by zero or taking the square root of a negative number shows an error.

Common mistakes to avoid

• Forgetting that % divides by 100. To add 10% to a price, multiply by 1.10 or use our Percentage Calculator.
• Mixing degrees and radians. Do not enter a radian value while the display says DEG.
• Typing a number right after an answer. That starts a new calculation, so press an operator first if you want to continue from the answer.
• Using x² when you mean 2x. The x² key squares the number. To double it, multiply by 2.

A good habit is to estimate the answer in your head before you press the equals key. If you expect a number near 50 and the screen shows 5,000, you probably typed an extra digit or used the wrong angle mode. A quick sanity check like this catches most input mistakes and builds your number sense over time.

Frequently asked questions

Is this calculator free?

Yes. It is free, needs no account and has no limits.

Does it work on a phone?

Yes. On a narrow screen the keys stack into two blocks, scientific functions on top and the number pad below, so every key stays large enough to tap.

How do I calculate a square root?

Press √x, type the number and press equals. The calculator closes the bracket for you. For example, √x then 144 gives 12.

How do I switch between degrees and radians?

Tap the DEG key. It changes to RAD, and the mode label in the top left of the display changes with it.

Is my information stored?

No. Everything is calculated in your browser, and nothing you type is sent to our server or saved.

Helpful resources

• Order of Operations (PEMDAS) from Math Is Fun
• Worked example: Order of operations from Khan Academy
• Our Percentage Calculator and Age Calculator for everyday math

This calculator is provided for general information and learning. Always double-check important results. See our Terms & Disclaimer.