Scientific Calculator Online Free — Complete Guide to All Functions

Basic vs Scientific mode

A basic calculator handles +, -, ×, ÷. A scientific calculator adds:

• Trigonometric functions (sin, cos, tan)
• Inverse trig (sin⁻¹, cos⁻¹, tan⁻¹)
• Logarithms (log base 10, natural log)
• Powers and roots (x², √, xʸ)
• Factorial (n!)
• Constants (π, e)

Trigonometric functions

DEG vs RAD mode

This is the most common source of errors.

• DEG mode: angles in degrees (0–360). Use for everyday geometry.
• RAD mode: angles in radians (0–2π). Use for calculus and physics.

sin(90°) = 1 in DEG mode sin(π/2) = 1 in RAD mode — same result, different input

Common trig values

Logarithm functions

• log(x): Logarithm base 10. log(1000) = 3 because 10³ = 1000
• ln(x): Natural logarithm (base e). Used in calculus, growth models
• 10ˣ: Antilog base 10. Inverse of log()
• eˣ: Exponential. Inverse of ln()

Factorial (n!)

n! = n × (n-1) × (n-2) × ... × 1

Examples:

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

Factorials grow extremely fast — 20! = 2.43 × 10¹⁸

Order of operations (PEMDAS/BODMAS)

The calculator follows standard math order:

1. Parentheses / Brackets
2. Exponents / Orders (powers and roots)
3. Multiplication and Division (left to right)
4. Addition and Subtraction (left to right)

Use parentheses to force a specific order:

• 3 + 4 × 2 = 11 (multiplication first)
• (3 + 4) × 2 = 14 (addition first due to parentheses)

Keyboard shortcuts

The calculator supports full keyboard input:

• 0–9 and . — number entry
• +, -, *, / — operators
• Enter — equals
• Backspace — delete last digit
• Escape — clear all