The calculator is used to test your eyesight and recognize the difference in color shades. After clicking on the first lighter field, the calculator will change colors and the countdown will begin. Each test takes 15 seconds. Search for a lighter field and click on it. Each subsequent test is more difficult. The test will be aborted if you do not give the correct answer within 15 seconds or if you make a wrong choice three times.

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

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.

With this calculator you will calculate the weighted arithmetic mean.

With the GUDERMANN trigonometric function calculator you can calculate the values of the hyperbolic amplitude. In addition to the response results, the calculator will also plot the selected function. You can choose a ready-made function, e.g. gd(x) or arcgd(x) as the inverse of the Gudermann function, or enter your own function, e.g. gd(x^2), gd(x+3), etc.

Pentagon calculator will help you calculate the long diagonal of the pentagon, the medium diagonal of the pentagon, the shorter diagonal of the pentagon, the side length, height, area of the pentagon, circumference and radius of the circumscribed circle and the radius of the circle inscribed in the regular pentagon.

The WHR calculator calculates the ratio of waist circumference to hip circumference.
Thanks to the Talia-Hips calculator, we will find out what type of obesity we have, what is the risk of hypertension, coronary diseases, stroke, atherosclerosis and diabetes, and we will learn the average standard WHR for our gender and age.

Are your hair falling out, are you starting to go bald? Use this calculator and check the probability and age at which you may be at risk of total hair loss.

Thanks to the 4x4 matrix math calculator, you can easily calculate the determinant of the matrix 4x4, find the complement 4x4 matrix, transpose 4x4 matrix, inverse 4x4 matrix.

With the Fractions Calculator, you can subtract any two mixed numbers or proper and improper fractions.
Fractions Calculator will show you the result of operations on fractions step by step and will give you explanations of the operations performed to subtracting fractions. You will learn how to simplify fractions, how to find a common denominator, how to find the least common multiple and the greatest common divisor.

This calculator is a complete tool to calculate the heat loss of your home Whit this calculator, we will find out what the heat losses are, e.g. through the ceiling, external walls, windows, floor in each room of our house, depending on the type of building material, number of layers, insulation and external temperature.

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

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

Use the Ishihara test to check if you suffer from color blindness, to what extent your defect is Protanopia or Deuteranopia, or maybe just insufficient differentiation between red and green shades. As a result, in addition to the diagnosis, you will have the opportunity to check how each of the Ishihara plates is seen by people with various visual impairments, and if you have a defect, they will allow you to see what is on the plates.

With this statistical calculator, you will learn how to calculate the lower quartile, middle quartile, and upper quartile of an interval resolution series.

With this statistical calculator, you will learn how to calculate the arithmetic mean of a distribution point series (grouped data).

Using this calculator, you can calculate the volume percent concentration, also called the volume percentage of chemicals in mixtures and solutions.

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

Using the calculator you can calculate the partial pressure according to Daltons law.

You can calculate step by step any system of linear equations, both homogeneous and inhomogeneous with any number of unknowns by the Cramer's method. As a result, in addition to the solution, you also get a complete analysis and presentation of calculations step by step.