A scientific calculator evaluates a whole expression at once — powers, roots, logarithms and trigonometric functions included — and respects the order of operations. You can type the expression on your keyboard or build it with the keypad, see a live preview of the answer as you go, and press = to print it on the history tape.
How to use the scientific calculator
- Choose Degrees or Radians if your expression contains trigonometry.
- Type the expression, or tap keys to insert functions such as sin( or log(. Closing parentheses you forget are added automatically.
- Watch the gray preview to the left of the result; it updates while you type.
- Press = or Enter. The result is stored as Ans and printed on the tape.
- Click a tape line to load that expression back for editing.
Keys and functions
| Key | Meaning | Example |
|---|---|---|
| sin, cos, tan | Trigonometric functions of an angle | sin(30) = 0.5 in degrees |
| sin⁻¹, cos⁻¹, tan⁻¹ | Inverse trig: the angle for a given ratio | sin⁻¹(0.5) = 30 |
| ln, log | Natural log (base e) and common log (base 10) | ln(2) ≈ 0.693147 |
| eˣ, 10ˣ | Exponentials | e^(1) ≈ 2.718282 |
| x², xʸ | Square and any power | 1.05^10 ≈ 1.628895 |
| √x, ∛x, ʸ√x | Square, cube and y-th roots | 8^(1/3) = 2 |
| x! | Factorial of a whole number | 10! = 3,628,800 |
| 1/x, |x| | Reciprocal and absolute value | 4^(-1) = 0.25 |
| π, e, Ans, EXP | Constants, last answer, × 10ⁿ | 2π ≈ 6.283185 |
How expressions are evaluated
The calculator follows the usual precedence: parentheses and functions first, then powers, then multiplication and division, then addition and subtraction. Two details trip people up:
- Powers stack from the right. 2^3^2 means 2^(3^2) = 2^9 = 512, not 8^2 = 64.
- A leading minus applies after the power. −3^2 = −(3^2) = −9. Type (−3)^2 if you mean 9.
Implicit multiplication works the way you write it on paper: 2π, 3(4 + 5) and 40tan(35) all multiply. If you want to see every step of a long arithmetic expression, the order of operations calculator breaks it down.
Worked examples
Height of a tree. You stand 40 m from a tree and measure a 35° angle up to its top. In degree mode type 40tan(35): the height is about 28.008 m.
Compound interest. $5,000 at 4% a year, compounded monthly for 3 years: 5000(1+0.04/12)^(12×3) ≈ 5,636.36.
Logarithm in base 2. log(8)/log(2) = 3, because 2³ = 8.
Degrees or radians?
A full turn is 360° or 2π radians, so 180° = π radians and 1 radian ≈ 57.2958°. Geometry and surveying problems usually use degrees. Calculus, physics formulas such as angular velocity, and most programming languages use radians. A quick check: sin(30) should be exactly 0.5 in degree mode; if you see −0.988, you are in radians.
Accuracy and limits
Calculations use double-precision floating point, which carries about 15–16 significant digits; results are displayed to 12. Tiny round-off from trigonometry, such as sin(180°) coming out as 1.2 × 10⁻¹⁶ instead of 0, is snapped to 0. Factorials work up to 170!, the largest that fits in a double (about 7.257 × 10³⁰⁶); for exact large factorials use the factorial calculator. More specialized tools for logarithms and trig functions explain each result in detail.
Frequently asked questions
How do I switch between degrees and radians?
Use the Degrees / Radians switch above the display. It controls sin, cos, tan and their inverses, so sin(30) is 0.5 in degree mode but about −0.988 in radian mode, because 30 radians is a very different angle from 30°.
What is the difference between log and ln?
log is the common logarithm with base 10, so log(1000) = 3. ln is the natural logarithm with base e ≈ 2.71828, so ln(e) = 1. For any other base, divide two logs: log(8) ÷ log(2) = 3.
How do I enter numbers in scientific notation?
Press EXP (or type E) between the number and its power of ten. 6.022E23 means 6.022 × 10²³ and 1.5E-4 means 0.00015. Very large and very small answers are shown in the same × 10ⁿ form.
What does the Ans key do?
Ans stores the last answer. If you press an operator right after =, the next expression starts with Ans automatically, which makes chained calculations quick. You can also tap Ans anywhere inside a new expression.
Why is tan(90) reported as undefined?
In degree mode the tangent of 90°, 270° or −90° does not exist because the cosine of those angles is 0 and tangent is sine divided by cosine. Rather than print a meaningless huge number caused by rounding, the calculator flags it.