# All online calculators

### Numerical integration

To calculate definite integral by the rectangle method, trapezoid method, Simpson method or other Newton-Cotes quadrature methods.

### Numerical integration with explicit Newton-Cotes formula coefficients

All weights must be separated by comma. A weight is a simple fraction in form of n/d, where n - numerator, d - denominator or real number. The first weight is a common multiplier, set 1 if there is no common multiplier.

Digits after the decimal point: 6

### One-variable function graph

This online calculator plots one-variable function graph given function formula and range of variable

### One-variable function graph

Digits after the decimal point: 2
• Parallel and perpendicular lines on a plane

This online calculator checks lines' slopes to see if they are parallel or perpendicular

• PBX channel number calculation

Calculates number of PBX telecommunications channels for given traffic load using Erlang B and Engset algorithms

• Pearson correlation coefficient

The calculation of the correlation coefficient of two random variables

• Percentage

This online calculator gives the percentage of the value. It also calculates the percentage of the sum (e.g. the income tax of the net salary) and the percentage of the difference (e.g. VAT of the gross amount).

• Petroleum product density

Petroleum product density conversion, according to GOST 3900-85

• Pipe cold bending. Flexure depth with main shaft.

Calculates the section flexure depth with pipe bender or bending machine to obtain given parameters.

• Playfair cipher

This online calculator encrypts and decrypts a message given Playfair cipher keyword. Non-alphabetic symbols (digits, whitespaces, etc.) are ignored.

• Points of the compass

This online calculator outputs compass point given direction angle in degrees. Different compass roses (4, 8, 16, 32, 128-wind compass roses) are supported.

## Calculator categories

 Life (48)
 Professional (145)
 Study (204)