History
Your calculations show up here. Click one to reuse the result.
How to use the scientific calculator
Type the whole expression the way you would write it on paper, then read the answer on the display. The buttons enter numbers and functions. Your computer keyboard works too: digits, operators, parentheses, and Enter to calculate.
- Enter numbers and operators: 2 + 3 × 4.
- For functions, open the parenthesis after the name: sin(30), √(81), log(1000).
- Check that the mode reads DEG (degrees) or RAD (radians) before using sine, cosine, or tangent.
- Use a period for decimals: 2.5 × 4 gives 10.
- Press = to lock in the answer and keep calculating from there.
For everyday math with prices, rates, and ratios, the percentage calculator and the proportion calculator show the steps.
Available functions
| Function | How to type | Example | Result |
|---|---|---|---|
| Sine | sin(x) | sin(30) in degrees | 0.5 |
| Cosine | cos(x) | cos(60) in degrees | 0.5 |
| Tangent | tan(x) | tan(45) in degrees | 1 |
| Common log (base 10) | log(x) | log(1000) | 3 |
| Natural log (base e) | ln(x) | ln(1) | 0 |
| Square root | √(x) | √(81) | 9 |
| Power | x^y | 2^10 | 1,024 |
| Square | x^2 | 9^2 | 81 |
| Pi | π | 2 × π | 6.2832 |
| Percent | x% | 100 + 10% | 110 |
Cube roots and other roots work through fractional exponents: the cube root of 27 is 27^(1÷3), which gives 3. For averages and spread, use the average calculator and the standard deviation calculator.
Degrees or radians
The DEG/RAD key sets the unit for angles. In degrees, a full turn is 360. In radians, a full turn is 2π (about 6.2832). The same angle gives the same sine in both units, but only when the number you type matches the mode.
| Angle | In degrees (DEG) | In radians (RAD) | sin | cos |
|---|---|---|---|---|
| 30° | 30 | π/6 | 0.5 | 0.8660 |
| 45° | 45 | π/4 | 0.7071 | 0.7071 |
| 60° | 60 | π/3 | 0.8660 | 0.5 |
| 90° | 90 | π/2 | 1 | 0 |
Order of operations
The calculator follows the standard order, often taught as PEMDAS: parentheses first, then exponents and roots, then multiplication and division (left to right), and last addition and subtraction (left to right).
| Expression | Steps | Result |
|---|---|---|
| 2 + 3 × 4 | 3 × 4 = 12; 2 + 12 | 14 |
| (2 + 3) × 4 | 2 + 3 = 5; 5 × 4 | 20 |
| 2 × 3^2 | 3^2 = 9; 2 × 9 | 18 |
| (2 × 3)^2 | 2 × 3 = 6; 6^2 | 36 |
| 10 − 4 − 3 | left to right: 6; 6 − 3 | 3 |
| 100 ÷ 5 ÷ 2 | 20; 20 ÷ 2 | 10 |
When in doubt, add parentheses. They cost one tap and remove the guesswork, especially in fractions like (1 + 2) ÷ (3 + 4), which without them would read as 1 + 2 ÷ 3 + 4.
Worked examples
| Problem | Type | Result |
|---|---|---|
| Height of a building: 50 ft away, angle of 30° | 50 × tan(30) | 28.8675 ft |
| Diagonal of a 3 ft by 4 ft shelf | √(3^2 + 4^2) | 5 ft |
| Savings: $1,000 at 1% a month for 12 months | 1000 × 1.01^12 | 1,126.825 |
| Price after 15% off $80 | 80 − 15% | 68 |
| How many digits in 2^100 | log(2^100) | 30.1030, so 31 digits |
For growth with regular deposits, use the compound interest calculator. To factor numbers, see the LCM and GCF calculator.
TI, Casio, and other models
Many people searching for a "TI-30" or "Casio scientific calculator" want an online stand-in. This page covers the core functions of a typical school scientific calculator: trigonometry, logarithms, roots, powers, parentheses, percent, and a degrees/radians mode.
- There is no off button. Close the tab when you are done.
- On an iPhone, the built-in calculator turns scientific when you rotate the phone sideways. This page works in any mobile browser with nothing to install.
- There are no variable memories (A, B, C, M) and no statistics mode with frequency tables.
- The page does not solve equations, matrices, complex numbers, or integrals, which are features of advanced models.
- Graphing calculators like the TI-84 plot graphs. This page does not.
- Tests such as the SAT, ACT, and AP exams publish their own lists of approved calculators, so check the current list before you bring a device.
Frequently asked questions
How do I use a scientific calculator?
Type the full expression with parentheses on functions: sin(30), √(81), 2^10. Check the DEG or RAD mode and press equals. Your computer keyboard works too.
How do I calculate sine, cosine, and tangent?
Type sin(x), cos(x), or tan(x) with the angle in parentheses. In degree mode, sin(30) is 0.5, cos(60) is 0.5, and tan(45) is 1. In radians, use π: sin(π/6) also gives 0.5.
What is the difference between degrees and radians on a calculator?
Degrees split a turn into 360 parts and radians use 2π. The DEG/RAD key sets how the angle you type is read. The same number gives different answers: sin(30) is 0.5 in degrees and −0.9880 in radians.
How do I find a square root or a power?
For a square root, type √(81) to get 9. For a power, use the caret: 2^10 gives 1,024. Other roots use a fractional exponent, like 27^(1÷3) = 3.
How does the percent key work?
Here, 100 + 10% gives 110 and 200 − 10% gives 180, like a pocket calculator. A percent sign on its own divides by 100, so 50% is 0.5. For full cases, use the percentage calculator.
Is this the same as a TI-30 or Casio, and how do I turn it off?
The page covers the core functions of a school scientific calculator, but not variable memories or the statistics mode. There is nothing to switch off online, so closing the tab is enough. For mean and standard deviation, use the dedicated pages.
Sources and method
- Order of operations and trigonometric functions (high school math)