How to use the scientific calculator
- Type an expression in the box, or press the keys. Results appear live as you type; press = or Enter to keep one in the history.
- Pick Degrees or Radians before using sin, cos or tan. Degrees is the default, because it is what most school and everyday problems expect.
- Use Ans to reuse the last answer, and click an item in the history to bring that expression back for editing.
You can use your keyboard directly. Operators are + − * / ^, brackets are ( ), and you may write pi and e as words. Implicit multiplication works, so 2(3+4) and 3pi are understood.
Order of operations
The calculator follows the standard order, often remembered as BODMAS or PEMDAS:
- Brackets, and the function arguments inside them.
- Factorials (
!), percent signs and powers (^). Powers group from the right, so2^3^2is 2^(3^2) = 512, not (2^3)^2 = 64. - Negation. A minus sign in front is applied after the power, so
-2^2is −4. Type(-2)^2to get 4. - Multiplication and division, left to right.
- Addition and subtraction, left to right.
A percent sign simply divides by 100, so 50% is 0.5 and 200*15% is 30. It does not change what a preceding plus means, which means 200+10% is 200.1, not 220. For a percentage change, use the percentage calculator.
Functions available
| Function | What it does | Example | Result |
|---|---|---|---|
| sin, cos, tan | Trigonometric ratios in degrees or radians | sin(30) | 0.5 |
| asin, acos, atan | Inverse trig, answers in the chosen angle unit | acos(0.5) | 60 |
| ln | Natural logarithm (base e) | ln(e) | 1 |
| log | Common logarithm (base 10) | log(1000) | 3 |
| sqrt, cbrt | Square root, cube root | sqrt(144) | 12 |
| n! | Factorial of a whole number up to 170 | 5! | 120 |
| abs, exp | Absolute value, e to a power | abs(-7) | 7 |
| floor, ceil, round | Round down, up and to nearest | round(2.5) | 3 |
Worked examples
- Compound growth: 1000 × (1 + 0.05)^10 = 1628.894627. The money grows by 62.9% in ten years at 5%.
- Right-angled triangle: a ladder 5 m long leans at 70° to the ground. The height reached is 5 × sin(70) = 4.69846310393 m.
- Combinations: choosing 3 items from 10 is 10! ÷ (3! × 7!) = 120.
- Natural log growth time: how long for an amount to double at 7% a year? ln(2) ÷ ln(1.07) = 10.2447 years.
- Floating-point clean-up: 0.1 + 0.2 shows 0.3, not 0.30000000000000004, because results are rounded to 12 significant digits.
Common angle values
| Angle | sin | cos | tan |
|---|---|---|---|
| 0° | 0 | 1 | 0 |
| 30° | 0.5 | 0.866025403784 | 0.577350269190 |
| 45° | 0.707106781187 | 0.707106781187 | 1 |
| 60° | 0.866025403784 | 0.5 | 1.73205080757 |
| 90° | 1 | 0 | undefined |
At exactly 90° the tangent is undefined, so the calculator says so rather than printing a huge meaningless number. In degrees mode, results within 10⁻¹² of zero are shown as exactly zero, so cos(90) gives 0 and not 6.1×10⁻¹⁷.
Tips for entering expressions
- Use brackets freely. They cost nothing and remove doubt: write (1+2)/(3+4) instead of 1+2/3+4.
- Close what you open. Typing sin( leaves a bracket open, and the calculator reports a missing bracket rather than guessing.
- Powers of ten: 3e8 means 3 × 10⁸, and 6.02e23 is a valid way to enter Avogadro's number.
- Roots other than square: the nth root of x is x^(1/n), so the cube root of 27 is 27^(1/3) = 3 (or cbrt(27)).
- Reusing answers: after pressing =, the result replaces the expression, so you can keep going with +5 or *2. Use Ans if you cleared the box.
Where each function is useful
| Task | Expression to type |
|---|---|
| Height of a ramp of length L at angle A | L*sin(A) |
| Distance along the ground for the same ramp | L*cos(A) |
| Angle of a slope with rise 3 and run 4 | atan(3/4) in degree mode gives 36.87 |
| Hypotenuse of a 5 by 12 right triangle | sqrt(5^2+12^2) gives 13 |
| Number of digits of a positive integer N | floor(log(N))+1 |
| Compound interest after t years at rate r | P*(1+r)^t |
| Time to grow by a factor of F at rate r | ln(F)/ln(1+r) |
| Orders of arrangement of 6 items | 6! gives 720 |
The trig keys treat angles as degrees by default. If you paste a formula from a physics or calculus textbook that uses radians, switch to Radians first, or the answers will be wrong by a factor of about 57.3.
Accuracy and limits
The calculator uses standard double-precision arithmetic, about 15 to 16 significant digits, and shows 12. It cannot do complex numbers, matrices, equations or graphs. Very large factorials stop at 170!, and results above about 1.8×10³⁰⁸ are reported as too large. Check any result that matters for safety, engineering or finance against a second method.
Frequently asked questions
Should I use degrees or radians?
Use degrees for everyday angles like 30° or 90°, and radians when a formula uses π, as in calculus and physics. The toggle above the keypad changes how sin, cos, tan and their inverses read and give angles.
Why does −2^2 give −4 and not 4?
Exponents are worked out before the minus sign, so it means −(2²). To square negative two, type (−2)^2.
Why is tan(90) undefined?
tan is sin divided by cos, and cos(90°) is zero. Dividing by zero has no value, so the result is reported as undefined.
How do I calculate a percentage of a number?
Type the number, a multiply sign and the percent, for example 250*12%. Because the percent sign divides by 100, this gives 30.
Does the calculator use eval()?
No. The expression is read by a small parser built for the purpose, so only numbers, operators and the listed functions are understood and nothing else can run.