Scientific Calculator
Free online scientific calculator
This scientific calculator handles everything from basic arithmetic to trigonometry, logarithms, powers, roots, and factorials. You can type directly into the display or use the buttons, switch between degrees and radians for trig functions, and press Enter or "=" to evaluate. It runs entirely in your browser, so it is fast, private, and free.
What it can do
Use it for order-of-operations arithmetic with brackets, trigonometric functions (sin, cos, tan and their inverses), natural and base-10 logarithms, square roots and arbitrary powers (xʸ), percentages, the constants π and e, and factorials. The angle-mode switch makes it suitable for both school trigonometry (degrees) and higher maths (radians).
More maths tools
For specific tasks, try our algebra solver, graph plotter, calculus solver, and trigonometry tool.
Frequently asked questions
Does it work in degrees or radians?
Both. Use the DEG/RAD switch above the display to choose. Degrees is the default and is what most school problems use.
How do I calculate a power?
Use the xʸ button (or type ^). For example, 2^10 gives 1024.
How do I find a cube root or other root?
Raise the number to a fractional power. A cube root is a power of 1/3, so type 27^(1/3) to get 3. A fourth root is ^(1/4), and so on. Remember the brackets around the fraction, otherwise the calculator works out 27^1 first and then divides by 3.
What is the difference between log and ln?
log is the base-10 logarithm, so log(1000) = 3 because 10³ = 1000. ln is the natural logarithm, base e (about 2.71828), so ln(e) = 1. Chemistry pH and decibel problems use log; growth, decay and calculus problems usually use ln.
Order of operations (BIDMAS / PEMDAS)
The calculator follows the standard order of operations taught in UK schools as BIDMAS and in the US as PEMDAS: Brackets, Indices (powers), Division and Multiplication from left to right, then Addition and Subtraction from left to right. So 2 + 3 × 4 gives 14, not 20, because the multiplication happens first. Type (2 + 3) × 4 if you want 20.
| You type | Result | Why |
|---|---|---|
| 2+3*4 | 14 | Multiplication before addition |
| (2+3)*4 | 20 | Brackets first |
| 2^3^2 | 512 | Powers stack from the right: 3² = 9, then 2⁹ |
| -(3^2) | -9 | The power is worked out, then made negative |
| (-3)^2 | 9 | Brackets make the whole −3 the base. Always bracket a negative base; typing -3^2 without brackets returns an error |
| 12/4*3 | 9 | Division and multiplication run left to right |
Worked examples
Trigonometry in degrees and radians
With DEG selected, sin(30) returns 0.5, the familiar exam value. Switch to RAD and the same input returns about −0.988, because the calculator now reads 30 as 30 radians (about 1,719 degrees). If a trig answer looks wrong, check the angle mode first; it is the most common calculator mistake in GCSE and A-Level maths. In RAD mode, sin(pi/6) gives 0.5, since π/6 radians is 30°.
Finding a missing side with Pythagoras
A right-angled triangle has shorter sides of 5 cm and 12 cm. The hypotenuse is √(5² + 12²). Type sqrt(5^2+12^2) and the calculator returns 13. Our guide to the 5-12-13 triangle explains why this particular set of numbers works so neatly.
Compound growth
£1,000 growing at 5% a year for 10 years becomes 1000 × 1.05¹⁰. Type 1000*1.05^10 to get 1628.89. For regular deposits and different compounding periods, use the savings and compound interest calculator.
Factorials and combinations
5! means 5 × 4 × 3 × 2 × 1 = 120, the number of ways to arrange five different items in a row. To count how many ways you can choose 3 items from 10 when order does not matter, use 10!/(3!*7!), which gives 120.
How the percentage button works
The % key simply divides the number before it by 100, so 15% becomes 0.15. That makes 200*15% equal 30, which is 15% of 200. Unlike some handheld calculators, 200+15% does not add 15% of 200; it gives 200.15. To increase a number by 15%, type 200*1.15 (230), and to decrease it by 15%, type 200*0.85 (170).
Tips and limits
- Results are shown to 12 significant figures, which is more than enough for school, university and engineering work.
- tan(90) in degree mode is undefined in exact maths, but because π can only be stored approximately, the calculator shows a very large number instead of an error. Treat any result above about 10¹⁵ from tan as "undefined".
- Factorials only work for whole numbers. Very large factorials (above 170!) exceed what a browser can store and return an error.
- Multiplication must be typed explicitly: write 2*pi rather than 2pi.
Everything runs in your browser and nothing you type is sent to a server. For step-by-step working, try the equation solver or our guide on solving simultaneous equations step by step.