Four-square cipher online encoder and decoder. Encrypt and decrypt any cipher created in a Four-square cipher. You can use any shift and additionally a key for more precise text encoding.

With this calculator you can calculate the density of the substance, i.e. specific mass. The calculator will also help to determine the mass of the substance and the volume it occupies.

Thanks to the calculator, you can easily calculate the area of a circle, the circumference of a circle, the area of a circle segment and the length of the circle arc.

Using the calculator, you can easily determine the daily need for carbohydrates, proteins and fats. As a result, the calculator will tell you how many calories and by weight you need per day and how many in each meal.

With this calculator, we will find out what ventilation efficiency should have depending on the size, height and type of room, e.g. in the kitchen, bathroom or toilet. The ventilation calculator will help us choose the right fan for the selected room, e.g. it will facilitate the selection of the hood for the kitchen.

With the converter, you can quickly translate any sentence into Morse code and vice versa. You can listen to the translated code, see it thanks to the light signals or, using the phone, feel it through vibration. Morse code is used nowadays mainly in amateur radio, it is also useful in many other areas of life.

With the COTANGENT trigonometric function calculator you can calculate the values of any cotangent function. In addition to the response results, the calculator will also plot the selected function. You can choose one of the preset functions, e.g. cotangent, cot² - cotangent square, arccot - arcus cotangent, coth - hyperbolic cotangent, arcoth - inverse function to coth, you can also enter your own function, e.g. cot(x) * cot(x) * cot(x) for cot³(x), cot(2x), cot(x+3), cot(x^2) etc.

Rail Fence, Zig-Zag cipher online encoder and decoder. Encrypt and decrypt any cipher created in a Rail Fence, Zig-Zag cipher.

You can calculate with explanations any system of linear equations, both homogeneous and heterogeneous with any number of unknowns by Gaussian elimination method. As a result, apart from the solution, you will also receive a complete analysis and a step-by-step calculation.

You can calculate any system of linear equations, both homogeneous and heterogeneous with any number of unknowns by Gauss-Crout elimination method.

Easily and quickly calculate the sum of the geometric sequence, you will determine the value of the nth term.

Calculate how much you spend smoking, so how much you could save after quitting smoking.

With this calculator you can quickly calculate the kinetic energy of an object. You will also calculate mass from energy and velocity and speed given kinetic energy and mass.

Affine cipher online encoder and decoder. Encrypt and decrypt any cipher created in a Affine cipher.

Regular polygon calculator will help you calculate the diagonals of any regular polygon, side length, height, area, perimeter and radius of the circumscribed circle and the radius of the circle inscribed in a regular polygon.

AtBash cipher online encoder and decoder. Encrypt and decrypt any cipher created in a AtBash cipher.

The calculator helps you to calculate the present value of money (PV) and the future value of money (FV) in time.

Using the calculator, you can calculate the pressure, volume, temperature and volume of moles of ideal gas.

With this calculator, you can calculate the resistance of the cable, knowing the material it is made of. You can also calculate the length of the conductor and the conductor diameter or the conductor cross-section area.

How to calculate your Maximum Heart Rate (HRMAX)? Which heart rate zones to choose for training and how to calculate the heart rate zones? At what heart rate is the best fat burning, and at what will we increase our efficiency and improve the condition? The calculator for maximum heart rate and heart rate zones can help answer these questions. You will calculate both your maximum and optimal heart rate and select the heart rate ranges for the appropriate training.