Convert-Me.Com - online units conversion

It would be handy for me if the site included the dimensional analysis of units; I was converting Kilowatts to hp, and noticed that a watt was '1 Joule per second'. Outstanding, but what the heck is a Joule? I went to it's conversion page... and saw it converted to watt seconds. This wasn't as helpful as I would have liked.

Meters per second probably doesn't need a dimensional analysis published; it is obviously m / s; no problem there... but it would be nice to know exactly how more complex (or at least just SI) units break down into fundamental units. 1 Watt = 1 kg m^2 / s^3 and 1 Joule = 1 kg m^2 / s^2 is sometimes exactly the info needed; please consider adding this.

Here's a site that has a free online dimensional analysis (a.k.a. factor-label method) calculator

xfactor.digins.com

Hi,

here is really good site for both conversions and physical constants calculations, which also does what you want,
after you get a result you can click simplify units to get the detailed units.

http://fermion.website.org

for example: if you type 1{J} you get 1 J you click simplify units and get 1 kg*m^2*sec^-2
to do a conversion you type 123{J}{eV} ...

also when you start typing a unit it gives you a list of available matching units to choose from.

tell me what you think.