Scientific Calculator
Type an expression or tap it out. The answer updates as you go, there is no equals key to press, and the link in the address bar carries your working so you can send it to someone.
You can type as well as tap. Parentheses are optional after a function, so sin 45 and sin(45) both work, and 2pi means two times pi. Use mod for a remainder, because % means percent here.
How the math works
The usual order of operations: parentheses first, then factorial and percent, then powers, then multiplication and division, then addition and subtraction. Powers group to the right, so 2^3^2 is 2^9 and not 8^2. Trigonometric functions read their angle in whichever mode is selected. Degrees is the default because that is what most questions are written in; switch to radians for anything from a calculus class. log is base ten and ln is base e. A percent sign after a number divides it by a hundred, so 15% is 0.15 and 200 * 15% is 30. For a remainder, write mod: 17 mod 5 is 2.
Common questions
- Why is there no equals key?
- Because the answer is already there. The expression is recalculated on every keystroke, so the number you see always belongs to the expression you see. Pressing Enter keeps a copy of the answer in the list on the right, which is the part an equals key was actually for.
- Is sin 45 in degrees or radians?
- Degrees, unless you switch the mode. Degrees is the default here because most people arriving at a calculator are working from a problem written in degrees, and getting 0.85 instead of 0.707 is the classic sign that the mode was wrong.
- Do I have to type the closing parenthesis?
- Not after a function. sin 45 and sin(45) both work. You do need them for grouping, as in (2+3)*4, and the calculator says so if one is missing rather than guessing.
- How do I do a percentage?
- Put the sign after the number. 15% on its own is 0.15, 200 * 15% is 30, and 200 + 200 * 15% is 230. The sign never means remainder here, so use mod for that: 17 mod 5 is 2.
- Can I share a calculation?
- Yes. The expression and the angle mode live in the address bar, so copying the link sends the whole piece of working rather than just the number. The link is read as an expression and never run as code, so a link from someone else can only ever show you a wrong answer, never do anything to your browser.
- What can it not do?
- Matrices, complex numbers, equations with an unknown to solve for, and graphing. It does arithmetic, powers and roots, trigonometry and its inverses, hyperbolic functions, logarithms, factorials, absolute values and rounding.