Unit Converter for Windows

Quad-Lock Unit Converter is a freeware tool for Windows that can take care of all your unit conversions within seconds. It contains more than 1000 units of measurements commonly encountered while solving engineering or everyday conversion problems. It includes a Search function to quickly find units, support for adding custom units, and a smart input box that evaluates calculations & complex expressions. Only the most common units are visible by default (e.g. Area, Distance, Temperature, Velocity) but hundreds more are included and easily found using Search.converter_screenshot

Distinctive Features:

  1. Simple & clean user-interface makes the learning curve non-existent to convert most measurements under the sun, even for inexperienced computer users.
  2. Fast and time efficient. There is no need for an installation package, no splash screen, and no silly registration or survey forms. The program is launched in less than a second, a Search function makes it easy to find any unit (even hidden ones), and conversions are performed instantly while typing input.
  3. The program can be run from a USB drive as a completely portable application, without leaving any personal data or registry settings behind.
  4. 100% spyware and adware free

Download Beta Version 6.0 for Windows

Requires: Windows 7 / Vista
Beta Version: 6.0 -see updates under Version History below
File Size: 1.54 MB (1,617,920 bytes)
MD5 Hash:D964F066DA6901DF4E052C4D116D61E0

Download Prior Version Unit Converter 5.4 for Windows

Requires:Windows 7 / 2000/XP/Vista Beta Version:5.4
File Size: 252 kB (258,560 bytes)
MD5 Hash:2C0C64FCDDAFA65689BAA255A626D7BB

View the Manual (pdf)

Author:Manu Mital (THANKS!)

Complete Terms of Use

Excerpt: This Site, the Materials and information accessible through this Site and the Software are provided “as is” without any representation or warranty, express or implied, of any kind, and Quad-Lock, its affiliates and their suppliers hereby disclaim all warranties and conditions with regard thereto, including, but not limited to, all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement, and those arising by statute or otherwise at law, or from a course of dealing or use of trade. Quad-Lock does not warrant that this Site or the Software will operate without interruptions or that it will be error free.

: For custom units and preferences to be stored, a small file named UnitConverter.ini (or after the name of your exe file) is written to the %APPDATA%\UnitConverter folder or, if running from a removable drive, to the removable drive’s root folder. You can transfer this file to other computers to transfer customizations.

Version History

Version 6.0:

  • Added Conversion History providing quick access to the 25 most recent unit conversions.
  • Added a ribbon menu with customizable quick access toolbar, and dockable windows for Search and the new Conversion History.
  • Added new category Currency with 38 world currencies. For the built-in currencies, the conversion rates are dynamically updated from the web (once per day) or by clicking the status bar or under menu Edit > Preferences > Currency tab.
  • Added ability to resize the window, e.g. to view more units
  • Added new category Permeability with 4 units.
  • Added cubic millimeters to Volume category.
  • Added ‘Clarke 1866 (NAD 27)’ to Coordinate transformations.
  • Added the name of the currently selected category to the window title (for easy task-switching when running multiple windows).
  • Minor revisions and corrections of several unit conversion factors in torque, pressure, and volume categories to improve accuracy of results.

Version 5.4:

  • Added ability to perform coordinate transformations from latitude/longitude to UTM (and vice-versa).
  • Added Heat Flux conversion category with 25 units
  • Added Magnetic Flux conversion category with 14 units
  • Added Volumetric Heat Generation category with 11 units
  • Added 6 new units to Fuel Consumption category (non-linear conversions such as Liters/100km to Miles/Gallon)
  • Corrected conversion factor in Amount of Substance; 1 mol = 1000 mmol, showed 1000000 mmol
  • Re-organized main menu. Also, added an icon next to each menu item.
  • Quad-Lock Converter now uses Unicode for the entire program (UI controls and the engine), enabling internationalization.
  • Removed restrictions such that users can now add an un-limited number of custom units and categories. Furthermore, users can also add non-multiplicative unit conversions (such as from Liters/100km to Miles/Gallon)
  • Changed location of UnitConverter.ini (preferences file) to the %APPDATA%\UnitConverter folder or, if running from a removable drive, to the removable drive’s root folder (e.g. F:\UnitConverter.ini).
  • User defined custom categories can now be rendered visible or invisible in the main window using Main Menu > Edit > Preferences
  • The conversion engine now uses a hash table to efficiently map unit names to associated conversion factors. This should improve speed on old and obsolete computers (the difference may not be noticeable on fast modern computers).

Version 5.3:

  • Added ability to ‘Find’ units and categories (Crtl + F)
  • Added ability to ‘Invert Selected Units’ (Ctrl + I or click middle icon)
  • Added ability to enter additional complex expressions in the Input Box, e.g. type: sin(4e-1)+cos(sqrt(7^3)) The converter evaluates the expression to 1.3356883 before performing the conversion.
  • Added Data Transfer category with 169 units
  • Added Numbers category with 35 numerical base conversions
  • Added 3 Enthalpy categories (Mass, Molar, and Volume) with a total of 17 units
  • Added Fuel Consumption category with 12 units
  • Added Amount of Substance category with 4 units
  • Added 15 new units to Data Category
  • Added 6 new units to Torque category
  • Added 6 new units to Volume category
  • Added 3 new units to SI Prefix category
  • Added gram/liter to Density category
  • Corrected conversion factor for ton-force (2000 lbf) in Force category
  • Changed location of UnitConverter.ini (preferences file) to the root drive (usually C:)

Version 5.2:

  • Added unit abbreviations wherever applicable (displayed underneath the results)
  • Added 76 new units to “Distance” category
  • Added 33 new units in the “Time” category and changed the baseline unit to alleviate some inaccuracies
  • Added Gill (UK) and Gill (US) to “Dry Volume” category
  • Corrected the conversion factors for miles/hour-min in “Acceleration” and for hectare in “Area”
  • Changed all unit names to lowercase, except when the name is based on a proper noun
  • Updated the Quad-Lock logo
  • Added the link “Check for update or donate” under the Help Menu

Version 5.1:

  • Added input support for fractions (e.g. use 1+3/8)
  • Revised Power Category – now over 70 units
  • Added SI Prefix Category – 15 new units
  • Added Data Category – 16 new units
  • Added Surface Tension Category – 11 new units
  • Added Concentration (Liquid) – 11 new units
  • Added Concentration (Molar) – 12 new units
  • Added Inductance – 21 new units
  • Added Radiation – 19 new units
  • Added Radiation Exposure – 11 new units
  • Added “Remember last used units” in addition to category on startup (enable under Preferences)

Version 5.0: original release