All online calculators

• Racing laps table

  This is generator of lap running order for kart racing. The goal is to let each racer to try each starting position/kart in random order.

• RAID arrays сalculator

  This calculators shows the possible variants of RAID arrays, based on the number of drives available.

• Rail fence cipher

  This article contains two calculators, first can be used to encode message with the rail fence cipher, second can be used to crack message encoded with the rail fence cipher by brute force. Decoded simply outputs decoded message for different number of "rails".

• Random combination of numbers from specified range

  This calculator randomly picks several numbers from specified range.

• Random Latin Quote

  Random Latin Quote

• Random Letters Generator

  This online generator just generates specified number of symbols, randomly selecting them from given set of symbols

• Raoult's Second law and the freezing temperature.

  Calculation of boiling point and crystallization (freezing) of non-electrolyte solutions.

• Rectangle area calculation by perimeter

  Rectangle area calculation with known perimeter and aspect ratio

• Region determination by the registration plate
• Regular expression tester

  This online calculator allows user to experiment with regular expressions.

• Regular polygon area from circumcircle

  Calculates the area of the circumcircle and of the regular polygon from radius of circumcircle and number of sides

• 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

• Relation between two numbers

  Different relations between two numbers. Created by user's requst

• Relations between the mass, the length, the width and the area density (surface density) of the fabric

  This online calculator calculates the mass of the fabric given the length, the width and the area density (surface density); the length of the fabric given the mass, the width and the area density; the width of the fabric given the mass, the length and the area density; the area density given the mass, the length and the width

• 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

• Relative luminance and contrast ratio

  Two calculators evaluate the relative luminance and contrast ratio for given colors.

• Release Date Countdown gadget

  This calculator allows you to configure the release date or event you want to track and use it as countdown gadget via new "Sharing" functionality

• Remove duplicates

  The calculator removes duplicates from an element list.

• Repeated Word Heatmap

  This calculator can help avoid unwanted word repetition in prose. It counts the number of occurrences of each word in the document, both globally, and within the "sliding window" distance before and after each word. It highlights the words which are used frequently near each other..