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Online Calculator

A fast, accurate calculator that works with your mouse, touch screen or keyboard. Switch to Scientific for powers, roots, trigonometry and logarithms; every result is saved to the history tape.

DEG

Type on your keyboard: numbers, + − * / ^ % ( ), Enter for =, Backspace, Esc to clear.

How to use the Online Calculator

Enter a calculation with the buttons or your keyboard, for example 12.5 × 4 + 3. The result preview updates as you type.
Press = or Enter to get the answer. Keep typing an operator to continue from the result, or a number to start fresh.
Use % for percentages: 80 − 15% takes 15% off 80.
Switch to Scientific for powers, roots, trigonometry (choose DEG or RAD) and logarithms.
Store numbers with M+ or M−, recall them with MR, and tap any line in History to reuse it. Press Copy to copy the result.

Order of operations (PEMDAS / BODMAS)

Step	Operation	Example	Result
1	Parentheses / brackets	(2 + 3) × 4	20
2	Exponents, roots, factorials	2 + 3²	11
3	Multiplication and division, left to right	12 ÷ 3 × 2	8
4	Addition and subtraction, left to right	10 − 4 + 1	7

Note that a minus sign in front of a power applies after the power: −2² = −4, while (−2)² = 4. Powers are evaluated from right to left, so 2^3^2 = 2^9 = 512.

Percent calculations made easy

You want	Type	Answer
Add 8% sales tax to $45	45 + 8%	48.6
Take 25% off $80	80 − 25%	60
15% tip on $62	62 × 15%	9.3
What percent is 18 of 72?	18 ÷ 72 × 100	25

Scientific functions

x², x³, xʸ: square, cube and any power. 2^10 = 1024.
√: square root. √(2) ≈ 1.41421356237. For other roots use a fractional power: the cube root of 27 is 27^(1÷3) = 3.
1/x: reciprocal, shown as ⁻¹. 4⁻¹ = 0.25.
n!: factorial, the product 1 × 2 × … × n, defined for whole numbers up to 170.
ln and log: natural logarithm (base e ≈ 2.71828) and common logarithm (base 10). log(1000) = 3.
×10ˣ: scientific notation. Large and tiny results are shown with E, so 1.5E12 means 1.5 × 10¹².

Frequently asked questions

Does the calculator follow the order of operations?

Yes. It uses the standard order of operations (PEMDAS/BODMAS): parentheses first, then exponents and roots, then multiplication and division from left to right, then addition and subtraction. For example 2 + 3 × 4 = 14, and (2 + 3) × 4 = 20.

How does the percent key work?

After + or −, a percentage is taken of the number before it, like a desk calculator: 50 + 10% = 55 and 80 − 15% = 68. After × or ÷, or on its own, % simply divides by 100: 200 × 10% = 20 and 10% = 0.1.

What keyboard shortcuts can I use?

Type digits and . for numbers, + − * / for the operators, ^ for powers, % for percent and ( ) for brackets. Enter or = calculates, Backspace deletes the last entry, Esc clears. In scientific mode s, c and t insert sin, cos and tan, l is ln, g is log, q is square root, p is π and ! is factorial.

Why does 0.1 + 0.2 show 0.3 here but 0.30000000000000004 elsewhere?

Computers store decimals in binary, so 0.1 + 0.2 is really 0.30000000000000004. This calculator rounds results to 12 significant digits before showing them, which removes these tiny binary errors without affecting normal calculations.

What is the difference between DEG and RAD?

They are the two units for angles. In DEG mode sin(90) = 1 because 90 means 90 degrees. In RAD mode angles are in radians, where π radians = 180°, so sin(π/2) = 1. Most school problems use degrees; calculus and physics often use radians.

How do the memory keys work?

M+ adds the current result to memory and M− subtracts it. MR inserts the stored number into your calculation and MC clears it. An M on the display shows that a value is stored. Memory and history are saved in your browser, so they are still there next time.

Is my history private?

Yes. All calculations run in your browser and the history tape is stored only on your device. Nothing is sent to a server. Use Clear to delete it.

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