Calculate with Scientific
Percent is postfix: 10% becomes 0.1.
Safe allowlisted parser · No eval() · Angles in degrees
Angle modes on the unit circle
DEG and RAD describe the same angle using different units. At 30° (π/6 radians), the point is approximately (0.866, 0.5).
Formula and variables
- x
- the function input
- f
- a selected scientific function
- y
- the evaluated result
Functions are evaluated inside parentheses. Exponents and postfix operators are resolved before multiplication, division, addition, and subtraction.
Domain note: Logarithms require positive inputs; real square roots require non-negative inputs; factorial requires a whole number from 0 to 170; inverse sine and cosine accept values from −1 to 1.
How to use this calculator
- 1
Choose DEG or RAD for trigonometric angles.
- 2
Build the expression with the keypad or keyboard.
- 3
Use 2nd to switch between trig and inverse trig functions.
- 4
Press equals to evaluate the allowlisted expression.
A complete example
Problem: Find sin(30°) + log(100).
Substitution: sin(30) + log(100)
Result: 0.5 + 2 = 2.5
In degree mode, sin(30°) is 0.5 and the common logarithm of 100 is 2.
Understand the result
Angle mode affects trigonometric and inverse-trigonometric functions only. Constants π and e use JavaScript’s double-precision mathematical constants.
Common mistakes
- Using degree input while RAD mode is active.
- Trying to calculate a real logarithm of zero or a negative number.
- Forgetting parentheses around a function argument.
Frequently asked questions
Does this calculator use JavaScript eval?
No. It uses a constrained parser that accepts only documented numbers, operators, constants, and functions.
What changes when I select RAD?
Trigonometric inputs are interpreted in radians, and inverse-trigonometric results are returned in radians.
Why is tan(90°) undefined?
Tangent is sine divided by cosine. At 90 degrees, cosine is zero, so the quotient is undefined.