- Count the number of words
The calculator counts word number in a given text. It can be used for rough calculation of translation cost. Can be used for word number calculation in software resources.

- Counting pipes from the end face
The approach to the calculation of the number of nested circles of smaller radius at a known length of the describing circle of a larger radius. Created by user request

- Course angle and the distance between the two points on loxodrome (rhumb line).
Calculation of a distance on loxodrome (rhumb line) and course angle (azimuth) between two points with a given geographical coordinates.

- Course angles and distance between the two point on the orthodrome(great circle)
Calculates the distance between two point of the Earth specified geodesic (geographical) coordinates along the shortest path - the great circle (orthodrome). Calculates the initial and final course angles and azimuth at intermediate points between the two given.

- Cramer's Rule
This online calculator solves system of linear equations using Cramer's rule and shows detailed steps of the solution

This online calculator calculates unknown (whether force, charge or distance) using known values using Coulomb's law scalar formula. It can be used to solve physics problems.

- Cryptarithmetic puzzle solver
This calculator is a solver of cryptarithmetic puzzles. Cryptarithmetic puzzle is a number puzzle in which a group of arithmetical operations has some or all of its digits replaced by letters or symbols, and where the original digits must be found. In such a puzzle, each letter represents a unique digit.

- Cube
- Cubic equation
Solution of cubic equation using Vieta's formulae. Created by user request

- Cylinder
- Cylindrical tank volume
Cylindrical tank volume

- Date and interval
Adds and subtracts a specified time interval to the specified date

This online calculator computes the result of addition/subtraction of the given number of days to the given date.

- Date and number of working days
Calculator calculates the date of the initial date and the number of working days. Taking into account weekends, holidays and weekend shifts at work days, according to the published decrees of the government of the Russian Federation. Created by user's request.

- Day of week by date
This online calculator outputs day of week for given date

- Density of oil
Recalculation of density of oil for different temperature and pressure values. Formulas are taken from Russia's GOST R 8.610-2004. "State system for ensuring the uniformity of measurements. Density of oil. The tables for recalculation" standard

- Derivative calculator
Online calculator which determines first derivative of a function

- Determinant of 3x3 matrices
This calculator calculates the determinant of 3x3 matrices

- Determinant of a matrix
This online calculator computes determinant of a matrix, using it's definition

- Determining air humidity with psychrometric method

Pages: