Do advanced maths in your browser. Trigonometry, logarithms, square roots, powers, pi and brackets — plus all the basic operations — in this free scientific calculator.
Trigonometry (sin, cos, tan) uses degrees, not radians. You can also type on your keyboard: numbers, + - * / ( ) and Enter for equals.
1. Type or click a number, a function (sin, cos, log, √) or a bracket. 2. Complete the expression and press = (or Enter). 3. Use C to clear and Backspace to delete. Angles for sin, cos and tan are in degrees.
A scientific calculator does everything a basic calculator does, plus the advanced maths that students, engineers and scientists need every day: trigonometry (sin, cos, tan), logarithms (log and ln), square roots, powers, pi and brackets. This free scientific calculator gives you all of that in your browser, with big buttons and keyboard support, so you can solve a homework problem, check an engineering formula, or work out a physics sum without installing an app or buying a device.
The most important thing to know is that the trigonometry buttons use degrees, not radians, because that is what school and college maths usually uses. So sin(30) is 0.5, cos(60) is 0.5, and tan(45) is 1. The log button is log base 10, the one used in pH, decibels and the Richter scale, while ln is the natural log, base e, used in growth and decay problems. The square root button gives √x, x² squares a number, and x^y raises a number to any power, for example 2^10 is 1024.
Suppose you need sin(30) plus the square root of 144. Click sin(, type 30, close the bracket, press +, click √, type 144, close the bracket, and press =. The answer is 12.5, because sin(30) is 0.5 and the square root of 144 is 12. Now try a power: 2^10. Click 2, click x^y, type 10, press =, and the answer is 1024. Try both in the calculator above and check that your results match 12.5 and 1024.
Take a real triangle problem: a ladder 5 metres long leans against a wall at an angle of 60 degrees to the ground. How high up the wall does it reach? The height is 5 times sin(60), because sin(angle) is opposite over hypotenuse. In the calculator, type 5, press ×, click sin(, type 60, close the bracket, press =. The answer is about 4.33 metres. Now try the base of the triangle: 5 times cos(60) is 2.5 metres. These two sums show why a scientific calculator matters: a basic calculator cannot do sin and cos at all.
Sin, cos and tan come from right-angled triangles. Sin(angle) is the opposite side divided by the hypotenuse, cos(angle) is the adjacent side divided by the hypotenuse, and tan(angle) is sin divided by cos. Log base 10 answers the question "10 to what power gives this number?" — log(100) is 2, because 10² is 100. Ln is the natural log, base e (2.71828): ln(e) is 1. The square root undoes squaring: √144 is 12 because 12² is 144. Pi (π) is 3.14159, the ratio of a circle's circumference to its diameter, and e is 2.71828, the base of natural growth. Powers follow the rule x^y, so 3^4 is 81.
Close your brackets. Every ( needs a ), or the calculator shows an error. Remember degrees, not radians. Sin(90) is 1 in degrees; in radians it would be different, so check your textbook's unit. Use log for base 10 and ln for base e. Mixing them up is the most common logarithm mistake. Use x^y for powers. For 2^10, type 2, x^y, 10, =. For a square, the x² button is faster. Check the display before pressing =. One wrong bracket or digit changes the whole answer, so read the expression first.
Forgetting to close a bracket. An unclosed bracket gives an error, so count your ( and ) before pressing =. Using radians by mistake. This calculator uses degrees for sin, cos and tan; if your problem uses radians, convert first (180 degrees is π radians). Mixing up log and ln. Log is base 10 and ln is base e — they give very different answers for the same number. Typing 2^10 as 210. The ^ key means "to the power of", so 2^10 is 1024, not 210. Dividing by zero. Any number divided by zero is not defined, so the calculator shows an error — check your numbers.
Pro Tip: Remember three values by heart: sin(30) = 0.5, cos(60) = 0.5 and tan(45) = 1. If your calculator gives those three answers, you know it is set to degrees and working correctly.
Note: This calculator uses degrees for trigonometry and base 10 for log. Results are rounded to 10 decimal places, so very small errors from floating-point maths are hidden.
Is this scientific calculator free? Yes, it is completely free, with no sign-up, no download and no limit on calculations.
Does it use degrees or radians for sin, cos and tan? Degrees. Sin(30) is 0.5 and tan(45) is 1, which is what school and college maths normally uses.
What is the difference between log and ln? Log is log base 10: log(100) is 2. Ln is the natural log, base e (2.71828): ln(e) is 1. They are used in different kinds of problems.
How do I calculate a power like 2 to the power of 10? Click 2, then the x^y button, then 10, then =. The answer is 1024. For a square, use the x² button instead.
How do I find a square root? Click the √ button, type the number, close the bracket and press =. For example, √(144) is 12.
Can I use brackets in my calculations? Yes. Brackets work normally, and the calculator follows the order of operations. Remember to close every bracket you open.
What is pi and when do I use it? Pi (π) is 3.14159, the ratio of a circle's circumference to its diameter. Use it for circle area (πr²), circumference (2πr) and many physics formulas.
Does it work on my phone? Yes. The buttons are large and touch-friendly, and the display is easy to read on a small screen. You can also use your keyboard on a computer.
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