Partner with

New Online Book! Handbook of Mathematical Functions (AMS55)
Conversion & Calculation Home >> Measurement Conversion

Measurement Converter Help

Introduction: The Measurement Converter is a sophisticated measurement conversion calculator that recognizes any combination of over 800 conversion factors, prefixes, constants, abbreviations, and synonyms.  Enter the measurement that you would like to convert from into the Convert From box, enter the measurement that you would like to convert to into the Convert To box (or leave it blank), then press the Convert It! button.

  • Natural Language: Measurements can be entered as English phrases or in a form similar to algebraic expressions.  For example, to convert from 10 cubic feet, enter the 10 cubic feet in the Convert From box.
  • Depth of Coverage: The Converter knows all of the important metric, SI, English, Avoirdupois, Troy, and ancient conversion factors. For example, converting 10 cups to liters returns 2.37.
  • Combination of Units: The Converter understands any combination of the known units and/or prefixes. For example, converting 45 ft*lbs/second^2 to Newtons returns 6.22.  Measurements like "acre-foot" can be entered by separating the units with an asterisk, as in acre*foot or acre*feet.  Measurements like "gallons per minute" can be entered as gallons per minute or by separating the units with a slash, as in gallons/minute.
  • Exponents (Square, Cubic, etc.): Powers can be entered using a caret ("^").  For example, square feet can be entered as feet^2 or ft^2, and cubic feet can be entered as feet^3 or ft^3.  Square feet can also be entered directly as square feet and cubic feet can also be entered directly as cubic feet.
  • Abbreviations and Synonyms: The Converter knows the abbreviations, full names, and common synonyms for the conversion factors. For example, "kilometers per hour" can be entered as kph, km/hr, kmeters/hour, kilometers/hour, kilometers per hour, etc.
  • Remaining Units: The Converter returns the remaining units if the dimensions of the units do not match. For example, converting 12 Joules to Newtons returns "12 meters".  Remaining units are returned in the standard SI units for the physical measurement. For example, results representing energy such as "kilowatt hours" are displayed in joules (the SI unit of energy).
  • Fractional Numbers: The Converter understand numbers expressed in either decimal form or as fractions.  For example, .2 gallons can be entered as 1/5 gallon.  You cannot enter fractions like "1 2/3 gallons" yet; we're working on it!
  • Currency/Exchange Rates: Use world currencies/current exchange rates within the measurement conversion calculator.  See this page for more information.
  • Results Box: All input expressions and results are shown along with the primary physical measurement that they represent.  For example, any measurements of the form "length per time" (e.g. miles per hour) are described as "speed".
  • Plural/Singular Forms: The Converter searches for unit definitions using the non-plural form of those names which may be plural. For example, a search for "Newtons" would first look for "Newtons" then look for "Newton" when that is not found.
  • Case-sensitivity: The Converter first tries to match each unit name using exact capitalization, then it tries to find a match using a case-insensitive search. For example, a search for "newton" would first look for "newton" then look for a unit whose capitalized name is "NEWTON" if "newton" were not found.
  • Overloaded Names: The Converter contains some definitions whose abbreviations are the same. In such cases, the abbreviations are capitalized differently. For example, it recognizes "m" to mean either "meter" when used alone, or to mean "milli" when immediately followed by a unit (as in "ml" which means "milliliters"), and it recognizes "M" to mean "mega" in all cases.  When in doubt about how to enter a measurement, try spelling out the names of the measurements you are trying to convert, or use abbreviations but review the results to make sure that the Converter interpreted your abbreviations correctly.
  • Multiple Prefixes Not Recognized: The Converter recognizes any combination of known prefixes and/or units. It will recognize "kilometers" as a combination of the prefix "kilo" and the measurement "meters". It does not recognize more than one prefix so, for example, it would not recognize "kilokilometers" as another way to represent "megameters".
  • Order of Evaluation: Within measurement expressions, division (as represented by the slash "/") has a lower precedence than multiplication (as represented by the asterisk "*"), unlike the rules of algebra where these operators have equal precedence.  So, the measurement expression m^2/V*s would be interpreted by the Converter as (m^2)/(V*s) and not as ((m^2)/V)*s.
  • Frequently Asked Questions: Additional help and documentation is available in the Measurement Converter Frequently Asked Questions (FAQ).

2000-2002, Inc. All rights reserved. is a Trademark of, Inc.

E-mail comments and questions to or post a message.