Scientific Calculator

What this calculator does

This calculator parses a mathematical expression written as text, applies standard operator precedence rules, and returns a numeric result with configurable decimal precision. It supports arithmetic operators (+, −, *, /, ^), parentheses for grouping, common trigonometric functions, logarithms, exponentials, square roots, absolute value, rounding functions, and the constants pi, e, and tau. The angle mode setting switches trigonometric functions between radians and degrees without changing anything else.

How expression parsing works

The expression parser tokenizes the input string into numbers, operators, function names, and parentheses, then builds an abstract syntax tree that respects the standard PEMDAS order: Parentheses, Exponents, Multiplication and Division (left to right), Addition and Subtraction (left to right). Functions like sin and log are applied to their arguments after the inner expression is fully evaluated. This means sin(pi/4)^2 correctly evaluates as (sin(pi/4))² rather than sin((pi/4)²), following mathematical convention.

Supported functions and constants

• Trigonometric: sin, cos, tan, asin, acos, atan (angle mode applies)
• Logarithmic: log (base 10), ln (natural log), exp (e raised to a power)
• Power and root: sqrt, pow(x,n), or the caret operator x^n
• Rounding: abs, ceil, floor, round
• Min / Max: min(a,b), max(a,b)
• Constants: pi (3.14159…), e (2.71828…), tau (6.28318…)

Interpreting results

• The result is displayed with the number of decimal places set in the precision field. The underlying computation always uses full 64-bit floating-point precision.
• NaN (Not a Number) appears for mathematically undefined operations such as sqrt(-1), log(0), or asin(2). This is the correct output: the calculator is not broken.
• Infinity appears when a computation exceeds numeric limits, such as 1/0 or a very large exponent. Check whether your expression is intended to produce a finite result.
• Very small results near zero may appear in scientific notation depending on the precision setting.

Real-world scenarios

• Unit conversion: convert 45 degrees to radians by typing 45 * pi / 180: result is 0.7854.
• Trigonometric identity check: verify sin(pi/4)^2 + cos(pi/4)^2 equals 1.
• Engineering formula: evaluate a compound expression like sqrt(3^2 + 4^2) to find the hypotenuse of a 3-4-5 triangle.
• Logarithm and decibel work: compute log(1000) to confirm it equals 3, or use ln for natural growth calculations.

Edge cases

• Division by zero: returns Infinity (or -Infinity for negative numerators), not an error. Use a conditional in your workflow if zero denominators are possible.
• log(0) and log(negative): returns NaN. The logarithm function is only defined for positive numbers.
• Very large exponents: 10^309 overflows to Infinity in standard 64-bit arithmetic.
• Mismatched parentheses: the parser returns a syntax error: check that every opening parenthesis has a matching close.