Available Functions
- Trigonometry — sin, cos, tan and their inverses (arcsin, arccos, arctan) in DEG or RAD mode
- Logarithms — log₁₀ (common logarithm) and ln (natural logarithm, base e)
- Powers & roots — x², xʸ (custom power), and √ (square root)
- Factorial — n! for calculating permutations and combinations
- Reciprocal — 1/x for quick reciprocal calculation
- Constants — π (pi ≈ 3.14159) and e (Euler's number ≈ 2.71828)
- Other — absolute value, sign toggle (±), percentage (%)
Degrees vs. Radians — When to Use Each
Angles can be measured in degrees (0–360) or radians (0–2π). The choice affects all trigonometric functions:
- DEG (Degrees) mode: Use for everyday geometry, navigation, architecture, and any problem where angles are given in degrees. Example: sin(90°) = 1.
- RAD (Radians) mode: Use for calculus, physics, engineering, and programming. Most programming languages (JavaScript, Python) use radians by default. Example: sin(π/2) = 1.
Conversion: Radians = Degrees × (π ÷ 180). Degrees = Radians × (180 ÷ π).
Understanding Logarithms
Logarithms answer the question "what exponent gives this value?"
- log₁₀(x): The common logarithm (base 10). log₁₀(1000) = 3 because 10³ = 1000. Used in pH, decibels, and the Richter scale.
- ln(x): The natural logarithm (base e). ln(e) = 1. Used in calculus, exponential growth/decay, and statistics.
Working with Powers and Roots
- x²: Squares the current value. Example: 7 x² = 49.
- xʸ: Raises x to any power. Enter base, press xʸ, enter exponent, press =. Example: 2 xʸ 8 = 256.
- √x: Square root. Example: √144 = 12.
- n!: Factorial. 6! = 6×5×4×3×2×1 = 720. Supports up to 170! before exceeding JavaScript's number precision.
Frequently Asked Questions
Why does sin(90) not equal 1 in my result?
Make sure you are in DEG (degrees) mode. If the calculator is in RAD mode, sin(90) means the sine of 90 radians, which is not 1. Switch to DEG mode and sin(90°) = 1.
Degrees vs Radians — which should I use?
Use DEG mode for everyday problems (geometry, navigation, construction). Use RAD mode for calculus, physics, and programming where π-based angles are standard.
How does xʸ work?
Enter the base (x), press xʸ, enter the exponent (y), then press =. Example: 2 xʸ 10 = 1024. For cube root, use xʸ with exponent 0.333 (or 1/3).
What is n! (factorial)?
Factorial multiplies a positive integer by all positive integers below it. 5! = 5 × 4 × 3 × 2 × 1 = 120. Factorials grow extremely fast: 20! ≈ 2.4 × 10¹⁸. This calculator supports factorials up to 170! before JavaScript's floating-point limit is reached.
What are π and e?
π (pi) ≈ 3.14159265... is the ratio of a circle's circumference to its diameter. It appears in geometry, trigonometry, and physics. e (Euler's number) ≈ 2.71828... is the base of the natural logarithm and appears in exponential growth, compound interest, and calculus.