OS X comes with a unit converter as a Dashboard Widget. Use Google in Safari’s search field and you can convert almost anything from anything to anything. Even OS X’s built-in calculator does conversions. Just open Calculator, and select the conversion you need from the Menubar.
Is there a better way?
No, not really. But there are options that might be more convenient for your Mac workflow. One that caught my eye over the weekend is called Convertos. It costs a few bucks but is handier than most because it lives in the Mac’s Notification Center as a widget in the Today section.
Click the Notification Center icon in the Menubar and, Voila! A conversion calculator appears.
As conversion calculators go, Convertos is no slouch, but it’s more traditional than an app that breaks new ground, despite living as a widget in the Notification Center. That makes it one-click handy.
What I’m not so sure of is the attention Notification Center gets vs. Dashboard Widgets. A widget is a widget, right? To get to Notification Center you need to move the mouse or trackpad pointer, then click on the Menubar, then scroll down to wherever the widget might be hiding among the mess of other notification cruft.
With the original Dashboard Widget, I set up a hot corner so all I need to do is move the mouse or trackpad pointer to a corner and, Voila! All the Widgets appear. That’s a more efficient system with less effort, more options. For whatever reason both Apple and app developers have abandoned the Dashboard Widget scene but using a hot corner or keyboard shortcut makes it more powerful.