The answer updates as you type — there is no equals key. Press Enter to keep a line in the history below.
Type an expression and read the answer. There is no equals key, because the result is already on screen by the time you would reach for one.
Where calculators disagree with each other, this page says which side it takes rather than leaving you to find out. 2^3^2 is 512, not 64. -2^2 is −4, not 4. 1/2x is half of x, not the reciprocal of 2x. Each of those has a defensible other reading, and the difference between them is not small.
It also declines to answer where there is no answer. tan(90) is undefined and says so; it does not return a number in the quadrillions. So does dividing by zero, the logarithm of a negative, and the arcsine of two. A calculator that answers "Infinity" has told you nothing and hidden which step went wrong.
Because powers group from the right: 2^3^2 means 2^(3^2) = 2^9 = 512. Reading it left to right would give (2^3)^2 = 64. Both answers exist in the wild, which is why it is worth knowing which one you are looking at. Use brackets if you mean the other.
Because the minus sign binds looser than the power, so it reads as -(2^2). This matches every scientific calculator and every programming language except spreadsheets — Excel gives 4 here and is essentially alone. Type (-2)^2 if you want the square of negative two.
Half of x. Implicit multiplication — writing 2x instead of 2*x — binds at exactly the same strength as an explicit divide, and evaluation runs left to right, so 1/2x is (1/2)·x. Some physics papers use the opposite convention where it means 1/(2x). The two differ by a factor of x², so use brackets whenever it matters.
Because π cannot be written exactly in binary, so the usual computation of sin(180°) lands a hair away from zero. The tiny number is not wrong, but it is not an answer either. In degree mode this calculator recognises the exact quarter turns and returns the exact value. Nothing else is rounded — a genuinely small result stays small.
Because the tangent of 90° is genuinely undefined — the line is vertical and has no slope. Answering "Infinity", or a number in the quadrillions, would suggest there is a value there. The same applies to dividing by zero, the logarithm of a negative number, and the arcsine of anything outside −1 to 1.
No, because there is nothing for it to do — the answer updates as you type. Enter files the current line into the history instead, and clicking any history line brings it back for editing.
Yes, and that is the intended way. Type the expression, read the answer, press Enter to keep it. The keypad exists for phones. It also accepts the × ÷ − symbols from a phone keyboard, and π and √ if you have them.
Every one of these is 64, 4 or 0.1667 on some calculator somewhere. Brackets settle the argument in every case, and cost nothing.
sin cos tan asin acos atan
sinh cosh tanh
sqrt cbrt abs exp ln log log2
floor ceil round sign mod min max
npr ncr x! pi e tau
Results are computed in double-precision floating point and displayed to twelve significant figures. Nothing you type here is sent to our servers — the calculation runs entirely in your browser.
