Scientific Calculator

Free online scientific calculator with trigonometric functions, logarithms, and more. Perfect for students and engineers.

Quick Reference

Trigonometry

sin, cos, tan - Trigonometric functions
asin, acos, atan - Inverse trig functions

Other Functions

log - Base 10 logarithm
ln - Natural logarithm
^ - Power/Exponent
√ - Square root
! - Factorial

What is a Scientific Calculator?

A scientific calculator goes beyond basic math to handle advanced operations like:

Trigonometry (sin, cos, tan)
Logarithms (log, ln)
Exponents and powers
Factorials
Constants (π, e)

Unlike basic calculators, scientific calculators follow order of operations (PEMDAS/BODMAS) automatically.

Degrees vs Radians

The angle mode matters for trigonometric functions:

Degrees (DEG) — The everyday mode

Full circle = 360°
Right angle = 90°
Most practical applications use degrees

Radians (RAD) — The mathematical mode

Full circle = 2π rad
Right angle = π/2 rad
Calculus and physics often use radians

\text{radians} = \text{degrees} \times \frac{\pi}{180}

If your trig calculations seem wrong, check your angle mode! sin(90) should equal 1 in DEG mode, but sin(90) ≈ 0.894 in RAD mode.

Trigonometric Functions

The basic trig functions relate angles to side ratios in right triangles:

Function	Definition	Common Values
sin(θ)	opposite/hypotenuse	sin(0°)=0, sin(90°)=1
cos(θ)	adjacent/hypotenuse	cos(0°)=1, cos(90°)=0
tan(θ)	opposite/adjacent	tan(0°)=0, tan(45°)=1

Inverse functions (asin, acos, atan) work backwards — they take a ratio and return an angle.

Understanding Logarithms

Logarithms answer the question: "What power do I raise the base to, to get this number?"

\log_b(x) = y \quad \text{means} \quad b^y = x

Common logarithms:

log (base 10): log(100) = 2 because 10² = 100
ln (base e): ln(e) = 1 because e¹ = e

Useful properties:

log(a × b) = log(a) + log(b)
log(a / b) = log(a) - log(b)
log(aⁿ) = n × log(a)

Exponents and Powers

The ^ operator handles powers:

2^3 = 8 (2 × 2 × 2)
10^-2 = 0.01
4^0.5 = 2 (square root)

Special cases:

Anything^0 = 1
Anything^1 = itself
0^0 = undefined (returns 1 by convention)

Factorials

Factorial (n!) multiplies all positive integers up to n:

n! = n \times (n-1) \times (n-2) \times ... \times 2 \times 1

Examples:

5! = 5 × 4 × 3 × 2 × 1 = 120
0! = 1 (by definition)
10! = 3,628,800

Factorials grow FAST — 20! already exceeds 2 quintillion!

Factorials only work with non-negative integers. 5.5! or (-3)! are undefined in standard math.

Order of Operations

Scientific calculators follow PEMDAS (or BODMAS):

Parentheses (Brackets)
Exponents (Orders)
Multiplication and Division (left to right)
Addition and Subtraction (left to right)

Example: 2 + 3 × 4 = 14 (not 20)

Calculator Tips

Memory functions:

MC — Clear memory
MR — Recall memory value
M+ — Add current value to memory
M- — Subtract current value from memory

Keyboard shortcuts:

Numbers and operators work as expected
Enter or = calculates result
Escape or C clears display
Backspace deletes last character