Units on the Web

Online unit conversion

There are many unit converters on the Web. They propose a limited set of units, often sorted by categories, among which the user can choose. To my knowledge, none of them makes it possible to the user to mix the units as he wishes. This is why I wrote , which rests on a different philosophy: the user writes the unit he wants, in the form of a mathematical formula.

My converter is not intended to be encyclopedic, but focusses on the units mostly used in physics and chemistry. The few conventional unit converters below often propose a much wider set of units, and should be sufficient for many purposes.

General conversions

Conversion of Units, from the Institute of Chemistry, Berlin
A long list of units there, but no categories
WWW Unit Converter, from digital dutch
Nice design, 11 categories
Javascript Unit Converter, by Costas Malamas
Quite fast, 20 categories
Convert2, from Legacy Systems
Quite slow, 26 categories
Conversion Factors, from Process Associates of America
40 categories, mainly for industry
Javascript Unit Conversion Calculator, by Ray Greaves
40 categories; many units there.
Measurements Converter, by Sergey Gershtein
9 categories
The MegaConverter, from Ben-Cam InterMedia
42 categories and links to specific converters (cooking, geology, ...)

Temperature conversion

Temperature Conversion Calculator, from the College of Chemistry
Kelvin, Celsius, Fahrenheit, Réaumur, Rankine
Temperature conversion program, by Jo Majd
Kelvin, Celsius, Fahrenheit
Temperature Converter, from the Bird Studies, Canada
Only Celsius and Fahrenheit

Currency conversion

The "Full" Universal Currency Converter[tm]
Updated every minute
Currency Calculator, by Jonathan Weesner
Daily rates, but a small number of currencies

Units and constants dictionaries

A Dictionary of Units of Measurement, by Russ Rowlett
A very complete and useful listing; gives a precise definition for all of the units
A Dictionary of Units, by Frank Tapson
Less complete than the preceding one; gives only conversion factors
The CODATA Internationally recommended values
A reference for physical constants
Table of Fundamental Physical Constants
A compact table of the CODATA recommended constants

Links

Comments and suggestions: C. Berthod