How This Calculator Evaluates Expressions
Unlike a basic calculator that applies each key as pressed, a scientific calculator parses the whole expression and applies the mathematical order of operations: parentheses, then functions and exponents, then multiplication and division, then addition and subtraction. Exponents associate right-to-left (2^3^2 = 2⁹ = 512), and implied multiplication like 2π or 3(4+1) is understood.
sin(30) + 2^10 / (4 − 2) in degree mode: sin 30° = 0.5; 2¹⁰ = 1024; 1024 ÷ 2 = 512; total 512.5.
Function Reference
| Button | Meaning | Example |
|---|---|---|
| sin, cos, tan | trigonometric functions (DEG/RAD) | cos(60) = 0.5 |
| log | logarithm base 10 | log(1000) = 3 |
| ln | natural logarithm (base e) | ln(e) = 1 |
| sqrt | square root | sqrt(144) = 12 |
| ^ | power | 5^3 = 125 |
| π, e | constants 3.14159…, 2.71828… | 2π = 6.2832 |
| abs | absolute value | abs(−7) = 7 |
For step-by-step explanations of individual operations, see the dedicated exponent and square root calculators — this page is the general-purpose workhorse, those pages teach the concepts.
Frequently Asked Questions
What is the correct order of operations?
Parentheses first, then exponents, then multiplication and division left to right, then addition and subtraction left to right (PEMDAS). This calculator applies these rules exactly — 2 + 3 × 4 is 14, not 20.
Should I use degrees or radians?
Degrees for everyday geometry and school problems (a right angle is 90°); radians for calculus and physics (a right angle is π/2). Use the DEG/RAD toggle — sin(30) is 0.5 in degrees but −0.988 in radians, so the mode matters.
What is the difference between log and ln?
log is base 10 (log 100 = 2, because 10² = 100); ln is the natural logarithm, base e ≈ 2.71828, which appears throughout growth and decay problems. They differ by a constant factor: ln x = log x × 2.3026.
Can I type instead of clicking buttons?
Yes — the expression field accepts full keyboard input including parentheses, ^ for powers, and function names like sin(, log(, sqrt(. Press Enter to evaluate.
Why does 0.1 + 0.2 show as 0.3 here?
Computers store decimals in binary, where 0.1 + 0.2 is internally 0.30000000000000004. This calculator rounds displayed results to 12 significant digits, which removes that binary noise while keeping far more precision than any practical use needs.
Cite This Calculator
Using this calculator in an assignment, article or lesson? Copy a ready-made citation — or the link snippet if you're referencing it from a web page.
The CalculatorsGuide Editorial Team. (2026). Scientific Calculator. CalculatorsGuide. Retrieved from https://www.calculatorsguide.com/math/scientific-calculator/