# All online calculators

- Regular polygon, number of sides and length of side from incircle and circumcircle radii
This online calculator finds number of sides and length of side of regular polygon given the radii of incircle and circumcircle

- Regular polygon. Incircle and circumcircle
This online calculator determines parameters of circumcircle and incircle of a regular polygon

- Relative humidity to absolute humidity and vise versa calculators
First calculator converts relative humidity to absolute humidity for given temperature and barometric pressure. Second calculator converts absolute humidity to relative humidity for given temperature and barometric pressure

- Root and power
This calculator outputs desired root and power of entered number

- Russian non-working days
The calculator displays official day offs for the current year and the weekends adjacent to them. The calculator takes into account weekends shifts according to Russian Federation Government Decrees.

- Saturation vapour pressure
This online calculator computes saturation vapour pressure for given temperature and atmospheric (barometric) pressure

- Seasonal fluctuations. Seasonal indices. Constant mean method.
The study of periodic (seasonal) fluctuations. Calculation of average seasonal index by constant mean method.

- Secant method
The secant method is a root-finding algorithm that uses a succession of roots of secant lines to better approximate a root of a function f.

- Shadow length
Gives a vertical object shadow length for given coordinates and time. Also calculates shadow growth during whole day.

- Shannon Entropy
This online calculator computes Shannon entropy for a given event probability table and for a given message

- Side length of a triangle
This calculator computes side length of a triangle given two sides and angle between them (law of cosines)

- Side length of the regular polygon
Calculates the side length of the regular polygon circumscribed or inscribed to a circle. Created by user's request

- Side of regular polygon from polygon area
Calculates the side length of regular polygon given the area of the regular polygon and number of sides

- Simple Interest
Calculates simple interest

- Simple math in any numeral system
This online calculator supports simple math (addition, subtraction, division, multiplication and power) for numbers expressed in any numeral system - binary, octal, hexadecimal, from the base 2 to base 36

- Sine wave
Construction of a sine wave with the user's parameters

- Solution of a system of 3 linear equations
Solution of a system of 3 linear equations with 3 variables

- Solution of buckets and tank problem
This online calculator find a solution to the question how to fill tank with certain amount of water using two buckets of different size