Free scientific calculator calculator
Evaluate complex expressions with trig, logarithms, exponentials, and roots — enter any expression to see the result, updated live, as you type.
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Uses JavaScript Math library (IEEE 754). Not a replacement for symbolic math systems.
Results are estimates. Consult a professional.
How the scientific calculator works
A scientific calculator extends basic arithmetic with trigonometric functions (sin, cos, tan and their inverses), logarithms (natural log ln and base-10 log), exponentials, square roots, and constants like π and e. This calculator evaluates mathematical expressions following standard order of operations (PEMDAS) and supports nested parentheses for complex calculations.
Worked example: compound expression with trig and logs
Evaluate the expression sin(30°) + log(1000) − ln(e²). This combines a trigonometric function, a base-10 logarithm, and a natural logarithm in one expression.
Common scientific calculator functions
The table below lists the most frequently used scientific calculator functions, their notation, and representative values.
| Function | Notation | Example | Result |
|---|---|---|---|
| Sine | sin(θ) | sin(90°) | 1 |
| Cosine | cos(θ) | cos(60°) | 0.5 |
| Tangent | tan(θ) | tan(45°) | 1 |
| Base-10 log | log(x) | log(100) | 2 |
| Natural log | ln(x) | ln(e) | 1 |
| Exponential | exp(x) or eˣ | exp(2) | 7.389 |
| Square root | √x | √144 | 12 |
| Power | x^y | 2^10 | 1024 |
Source: Standard mathematical function definitions. Trig functions assume degree mode unless otherwise specified.
Tips for using a scientific calculator accurately
Even with a reliable calculator, common input mistakes can produce wrong answers. These five habits prevent the most frequent errors.
- Always check degree vs. radian mode — sin(90) gives 1 in degrees but 0.894 in radians. Most everyday problems use degrees; physics and calculus typically use radians. Confirm the mode before computing.
- Use parentheses liberally — 1/2x is ambiguous: it could mean (1/2)×x or 1/(2x). Explicit parentheses make the order of operations unambiguous and prevent order-of-operations errors.
- Remember that log() means log base-10, not ln() — on most scientific calculators the "log" key is base-10; the natural logarithm uses the "ln" key. Mixing them up is the most common logarithm error.
- Use the memory or ANS key for chain calculations — storing intermediate results prevents rounding errors from manual re-entry and keeps your expression readable.
- Verify with a sanity check — for trig results, remember sin and cos always fall between −1 and 1. For logs, log(x) is positive only when x > 1, and negative when 0 < x < 1. A quick mental check catches most errors.
Accuracy and limitations
This calculator uses JavaScript's built-in Math library, which follows the IEEE 754 double-precision floating-point standard. Results are accurate to approximately 15–16 significant digits. Floating-point representation means some expressions produce small rounding errors — for example, 0.1 + 0.2 returns 0.30000000000000004 rather than exactly 0.3. For most scientific and engineering purposes, this precision is more than sufficient.
Domain restrictions apply: log and ln are undefined for non-positive numbers; arcsin and arccos are only defined for inputs between −1 and 1; square root is undefined for negative real numbers. Entering out-of-domain values will produce NaN (Not a Number).
Key terms
About this calculator
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