The metric system is, at its heart, about efficiency. With the metric system you don't have to remember units or convert from one measure to another - everything is in one place and the units and conversions are all laid out for you in a logical and user-friendly way. This free extension for Google Chrome will allow you to turn anything from a website to a recipe into your preferred metric units. You can use it to convert from the imperial system to the metric system with a quick click.

You can select things to turn into units of mass or volume and have them appear in a small toast at the top right of your page. For example, selecting a teaspoon of sugar will turn into a metric gram of sugar. It will also show you any necessary units or conversion you need to know for that value. When you're ready to set things back to imperial, simply click the icon again and it will be deactivated.