How to use the scientific calculator
- Check the angle unit first. The DEG key switches to RAD and back; the current unit is also shown at the top left of the display. Use degrees for everyday angles and triangle problems, radians for calculus and physics formulas.
- Tap the keys, or click the display and type. You can paste a whole expression too, such as
(4.5+2)×3^2. While you type, a grey preview shows the answer so far. - Press = or Enter to get the result. It also goes into the History list, where a tap loads the calculation again and the arrow button inserts just the result.
- To keep going, press an operator: the calculator continues from Ans, the last answer. Press a number to start a fresh calculation instead.
- Function keys open a bracket for you: sin types
sin(, so enter the angle and press = (missing closing brackets at the end are added automatically). Press 2nd to turn sin, cos and tan into sin⁻¹, cos⁻¹ and tan⁻¹ for one use. - Use ⌫ to delete the last character or function, AC (or Esc) to clear the line, and the copy button in the display to copy the plain result, for example
1.23e+21. - Memory: M+ works out the current line and adds it to memory, M− subtracts it, MR inserts the stored value and MC clears it. For example, 5 M+ 3 M+ MR gives 8.
Order of operations (PEMDAS / BODMAS)
The calculator reads a whole line the way maths textbooks do, not strictly left to right. Brackets come first, then powers and roots, then multiplication and division, then addition and subtraction. The two acronyms say the same thing: PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction) in the US and BODMAS or BIDMAS (Brackets, Orders or Indices, Division and Multiplication, Addition and Subtraction) in the UK.
| You type | Result | Why |
|---|---|---|
2+3×4 | 14 | Multiplication before addition: 3×4 = 12, then 2+12. |
(2+3)×4 | 20 | Brackets first: 5×4. |
2^3^2 | 512 | Powers group from the right: 2^(3^2) = 2^9. |
−3² or -3^2 | −9 | The power applies before the minus sign: −(3²). |
(−3)² | 9 | Brackets make the minus part of the number. |
10−4−3 | 3 | Same-rank operations go left to right: (10−4)−3. |
6÷2(1+2) | 9 | A number next to a bracket means multiply, with the same rank as × and ÷, so it is 6÷2×3. |
You can leave out the × sign between a number and a bracket, constant or function: 2π, 3(4+1), (1+2)(3+4) and 2sin(30) all work. This implied multiplication has the same rank as an ordinary ×, which is why 6÷2(1+2) gives 9. Some calculators give implied multiplication a higher rank and would show 1, so add brackets whenever a line could be read two ways.
Two more rules: n!, %, x² and 1/x apply to the number or bracket just before them, and % simply divides by 100. So 50% is 0.5 and 200×15% is 30. Unlike some phone calculators, 50+10% means 50 + 0.1 = 50.1; to add 10% to 50, type 50×1.1 or use the percentage calculator.
Degrees or radians?
A full turn is 360 degrees or 2π radians, so 180° = π rad and 1 rad ≈ 57.2958°. Degrees are what you use for triangles, slopes, bearings and most school geometry: in DEG mode, sin(30) = 0.5 and tan(45) = 1. Radians are the natural unit in calculus, physics and programming, where formulas like the arc length s = rθ assume the angle is in radians: in RAD mode, sin(π/2) = 1. Typing sin(30) in RAD mode gives −0.988, the sine of 30 radians, which is the most common reason a trig answer looks wrong. The inverse functions sin⁻¹, cos⁻¹ and tan⁻¹ return their answer in the selected unit, so sin⁻¹(0.5) is 30 in DEG mode and 0.5236 (π/6) in RAD mode.
Functions reference
| Key | What it does | Example |
|---|---|---|
| sin, cos, tan | Sine, cosine and tangent of an angle in the selected unit | sin(30) = 0.5 (DEG) |
| 2nd → sin⁻¹, cos⁻¹, tan⁻¹ | Inverse trig: the angle for a given ratio (type asin, acos, atan) | cos⁻¹(0.5) = 60 (DEG) |
| x², xʸ | Square; any power (^) | 2^10 = 1024 |
| √, ∛ | Square root (sqrt) and cube root (cbrt) | √(16) = 4, ∛(27) = 3 |
| log, ln | Logarithm base 10; natural logarithm (base e) | log(1000) = 3, ln(e) = 1 |
| 10ˣ, eˣ | 10 or e raised to a power, the inverse of log and ln | 10^(3) = 1000 |
| 1/x | Reciprocal, shown as ⁻¹ | 4⁻¹ = 0.25 |
| n! | Factorial of a whole number from 0 to 170 | 5! = 120, 0! = 1 |
| π, e | Pi (3.14159…) and Euler’s number (2.71828…) | 2π = 6.28319 |
| EXP | Times ten to the power of, for scientific notation | 1.5 EXP 3 → 1.5E3 = 1500 |
| Ans | The last result | Ans×2 |
| ± | Changes the sign of the last number | 5 ± → −5 |
When typing, 1e3 or 1E3 also means 1×10³. A lowercase e that is not followed by digits is the constant e, so 2e is 2×e. Square brackets work like round ones, and ** is accepted as a power.
Accuracy and rounding
Like almost every calculator and spreadsheet, this one works with 64-bit binary floating-point numbers, which carry about 15 to 17 significant digits. Many decimals, such as 0.1, have no exact binary form, so raw arithmetic gives tiny errors like 0.1+0.2 = 0.30000000000000004. To hide that noise, every result is rounded to 15 significant digits, so you see 0.3, and Ans and memory keep that rounded value. In degree mode, sine, cosine and tangent return exact values at the standard angles (sin 30° = 0.5, cos 90° = 0, tan 45° = 1), and tan(90°) shows an error because it is undefined. Very large or very small results switch to scientific notation, for example 1.23 × 10²¹ for 1,230,000,000,000,000,000,000. Factorials stop at 170! because 171! is larger than the biggest number a double can hold (about 1.8 × 10³⁰⁸); non-whole numbers have no factorial here.
The calculator uses a point as the decimal separator in every language, and spaces are used only to group digits in the big result. For unit conversions, use the dedicated cm to inches converter or kg to lbs converter; for Roman numerals, the Roman numeral converter. More calculators and converters are in Everyday Tools.
Private and works offline
Every calculation runs in your browser; nothing you type is sent to a server. Your last 20 calculations, the memory value and the angle unit are saved in your browser's local storage on this device so they survive a reload. Clear history and MC remove them.
Frequently asked questions
How do I use sin, cos and tan in degrees?
Make sure the angle key shows DEG (tap it to switch from RAD), then press sin, enter the angle and press =, for example sin(30) = 0.5. If you get −0.988 for sin(30), the calculator is in radian mode.
Why does my calculator say 2+3×4 = 14?
Because multiplication comes before addition in the standard order of operations (PEMDAS or BODMAS): 3×4 = 12, then 2+12 = 14. If you want 20, put the addition in brackets: (2+3)×4.
How do I calculate a square root or cube root?
Press √ for a square root or ∛ for a cube root, enter the number and press =: √(16) = 4 and ∛(27) = 3. You can also type sqrt(16) or cbrt(27). For other roots, use a fractional power, for example 16^(1/4) = 2 for the fourth root.
What is the difference between log and ln?
log is the logarithm base 10, so log(1000) = 3 because 10³ = 1000. ln is the natural logarithm, base e (about 2.71828), so ln(e) = 1. Their inverses are 10ˣ and eˣ. To get a logarithm in any other base, divide: log₂(8) = log(8)÷log(2) = 3.
How do I type an exponent?
Use the xʸ key or type ^: 2^10 = 1024. For squares there is x², and for scientific notation use EXP or type E, so 3E8 means 3×10⁸. Powers group from the right, so 2^3^2 = 2^9 = 512.
Is this scientific calculator free and does it work offline?
Yes. It is free with no sign-up, and all the maths runs in your browser. Once the page has loaded, it keeps working if your connection drops, and your history stays on your device.
Updated