How to use this scientific calculator
- Type an expression with the buttons or your keyboard, for example 2 + 3 × 4 or sin(30).
- Watch the faded preview under the expression: it shows the answer as soon as the expression is complete.
- Press = (or Enter) to keep the answer. It moves to the big line and into the history.
- Use Ans to reuse the last answer, and the memory keys (M+, M−, MR, MC) to keep a running total. Your history is saved in this browser so it is still there next time (use Clear history to delete it). Memory (M+, M−, MR, MC) lasts until you leave the page.
On a phone, switch between Basic and Scientific to show or hide the function keys.
Degrees vs radians
Angles can be measured in degrees (a full turn is 360°) or radians (a full turn is 2π). Use DEG for everyday geometry, building and navigation: sin(30) = 0.5 and tan(45) = 1. Use RAD for calculus, physics formulas and anything written with π, such as sin(π) = 0 or cos(π/3) = 0.5. The mode is shown in the corner of the display, and the inverse functions answer in the same unit: sin⁻¹(0.5) is 30 in degrees and about 0.5236 in radians.
Order of operations
The calculator follows the standard order of operations, often remembered as PEMDAS or BODMAS: brackets first, then powers and roots, then multiplication and division, then addition and subtraction, working left to right within each level.
- 2 + 3 × 4 = 14, because the multiplication happens first (3 × 4 = 12, then 2 + 12). Brackets change that: (2 + 3) × 4 = 20.
- 2^3^2 = 512, because stacked powers are worked out from the top down: 3² = 9, then 2⁹ = 512.
- −3² = −9, because the power comes before the minus sign. (−3)² = 9.
- 2π and 2(3 + 1) are read as multiplication, so you can leave out the × sign.
Trig, logs, powers and roots
sin, cos and tan relate an angle in a right-angled triangle to the ratio of two of its sides. sin(30°) = 0.5 means the side opposite a 30° angle is half the length of the longest side. The inverse functions (press 2nd for sin⁻¹, cos⁻¹ and tan⁻¹) go the other way, from a ratio back to an angle: sin⁻¹(0.5) = 30°. tan(90°) has no value, so the calculator shows Undefined.
Logarithms answer “what power gives this number?”. log(1000) = 3 because 10³ = 1000, and ln(e) = 1 because ln uses the base e ≈ 2.718. Logs only exist for numbers above 0.
Powers and roots: x² squares a number (5² = 25), xʸ raises it to any power (2^10 = 1024), √x finds the square root (√16 = 4), ³√x the cube root (³√27 = 3), and ʸ√x any root (8 ʸ√ 3 = 2). eˣ and 10ˣ raise e or 10 to the power you type next.
Factorials and scientific notation
A factorial multiplies all the whole numbers from 1 up to n: 5! = 5 × 4 × 3 × 2 × 1 = 120. Factorials grow very quickly, so 170! is the largest a browser can hold and 171! shows Too large.
Scientific notation writes very big or very small numbers as a number times a power of 10. Press EXP to enter one: 2 EXP 3 = 2 × 10³ = 2000. Results beyond about a quadrillion, or smaller than a billionth, are shown the same way, for example 1.23e+25.
Keyboard shortcuts
| Key | Does | Key | Does |
|---|---|---|---|
| 0–9 . | Numbers | s c t | sin, cos, tan |
| + - * / | Operators | l / n | log / ln |
| ^ | Power | r | Square root |
| ( ) | Brackets | p / e | π / e |
| % ! | Percent, factorial | Enter or = | Equals |
| Backspace | Delete last | Esc | Clear (AC) |
With 2nd switched on, s, c and t enter sin⁻¹, cos⁻¹ and tan⁻¹.
Frequently asked questions
Why does sin(30) give a strange answer?
Check the angle mode. In degrees (DEG), sin(30) is 0.5. In radians (RAD), 30 means 30 radians, so the answer is about −0.988. The current mode is shown in the top-left corner of the display, and the DEG / RAD key switches it.
What does the EXP key do?
EXP enters a number in scientific notation. 2 EXP 3 means 2 × 10³, which is 2,000, and 6.02 EXP 23 is 6.02 × 10²³. It is a shortcut for typing × 10^.
Why is −3² equal to −9 and not 9?
Powers are worked out before the minus sign is applied, so −3² means −(3²) = −9. To square negative three, use brackets: (−3)² = 9. This follows the standard order of operations used in maths and in most scientific calculators.
What is the largest factorial the calculator can work out?
170! is the largest, about 7.26 × 10³⁰⁶. 171! is bigger than the largest number a browser can store, so the calculator shows Too large. Factorials only work for whole numbers of 0 or more.
Does the calculator save my calculations?
Your last 50 calculations are saved only in this browser, so they are still there when you come back. They never leave your device and we can’t see them. Use Clear history to delete them. Memory (M+, M−, MR, MC) is not saved and clears when you leave the page.