Why do I get a different result for sin(30)?

Check the angle mode. sin(30°) = 0.5 in degree mode, but sin(30 radians) ≈ −0.988 — and 30 radians is approximately 1719°, far past one full rotation.

Does the calculator handle complex numbers?

No. Only real-valued arithmetic is supported. Square roots and even-power roots of negative numbers return 'Error'. For complex math, use a CAS such as Wolfram Alpha, SymPy, or your scientific software of choice.

How do I compute log base 2?

Use the change-of-base formula: log₂(x) = ln(x) / ln(2) = log(x) / log(2). For example, log₂(8) = ln(8) / ln(2) = 2.0794 / 0.6931 = 3.

What is the largest factorial I can compute?

JavaScript's number type can represent factorials up to 170! ≈ 7.26 × 10³⁰⁶. 171! overflows to Infinity. For arbitrary-precision factorials, use a BigInt library outside this calculator.

Can I store intermediate results?

Yes — the M+, M−, MR, MC memory buttons store and recall a single value. The history panel additionally keeps a record of every completed expression; click any entry to load it back into the editor.

How precise are trigonometric values?

About 15 significant decimal digits, the IEEE-754 double-precision limit. Values such as sin(180°) round to a tiny non-zero number rather than exactly zero — this is normal floating-point behaviour and visible only in very small magnitudes.

Scientific calculator

Trigonometry, logarithms, powers, and constants in one place.

A free online scientific calculator covering trigonometry (sin, cos, tan and their inverses), logarithms (log, ln), exponents, factorials, roots, percentages, and the core mathematical constants π and e. Supports degree and radian modes, full operator precedence, and a calculation history for replay and copy.

Function reference

Trigonometric functions (sin, cos, tan, sin⁻¹, cos⁻¹, tan⁻¹) accept either degrees or radians. Toggle the angle-mode switch before entering values — leaving it on the wrong mode is the most common source of unexpected results.

log denotes the base-10 logarithm; ln denotes the natural logarithm (base e). For other bases, use the change-of-base formula: log_b(x) = ln(x) / ln(b) = log(x) / log(b).

Operator precedence follows standard mathematics: parentheses bind tightest, then unary minus, then exponentiation (^), then multiplication and division, then addition and subtraction. When two operators share precedence, evaluation proceeds left to right.

Powers can be entered with the ^ operator (e.g. 2^10 = 1024) or via the dedicated x² and xʸ buttons. Square root, cube root, and arbitrary nth root are available as functions; nth root is computed as x^(1/n).

Constants π (≈ 3.14159265) and e (≈ 2.71828183) are available as buttons and can be used inside any expression. The factorial operator (!) accepts non-negative integers up to about 170 before overflowing to Infinity.

Identities worth remembering

Pythagorean identity: sin²(θ) + cos²(θ) = 1.

Logarithm rules: log(ab) = log(a) + log(b); log(aⁿ) = n × log(a); log_b(x) = ln(x) / ln(b).

Exponent rules: aᵐ × aⁿ = aᵐ⁺ⁿ; (aᵐ)ⁿ = aᵐⁿ; a⁰ = 1 for any non-zero a.

Euler's identity: eⁱπ + 1 = 0 (the calculator does not handle complex numbers, but the identity is useful context for radian-mode work).

Frequently asked questions

Why do I get a different result for sin(30)?: Check the angle mode. sin(30°) = 0.5 in degree mode, but sin(30 radians) ≈ −0.988 — and 30 radians is approximately 1719°, far past one full rotation.
Does the calculator handle complex numbers?: No. Only real-valued arithmetic is supported. Square roots and even-power roots of negative numbers return 'Error'. For complex math, use a CAS such as Wolfram Alpha, SymPy, or your scientific software of choice.
How do I compute log base 2?: Use the change-of-base formula: log₂(x) = ln(x) / ln(2) = log(x) / log(2). For example, log₂(8) = ln(8) / ln(2) = 2.0794 / 0.6931 = 3.
What is the largest factorial I can compute?: JavaScript's number type can represent factorials up to 170! ≈ 7.26 × 10³⁰⁶. 171! overflows to Infinity. For arbitrary-precision factorials, use a BigInt library outside this calculator.
Can I store intermediate results?: Yes — the M+, M−, MR, MC memory buttons store and recall a single value. The history panel additionally keeps a record of every completed expression; click any entry to load it back into the editor.
How precise are trigonometric values?: About 15 significant decimal digits, the IEEE-754 double-precision limit. Values such as sin(180°) round to a tiny non-zero number rather than exactly zero — this is normal floating-point behaviour and visible only in very small magnitudes.