This app calculates the relative sizes (either mass or diameter) of the major objects in the solar system. Simply enter a numerical value, the "From" units, the "To" units, and hit the "Convert" button.
For example, quickly calculate how many earth diameters there are in a solar diameter, or how massive Jupiter is relative to Saturn. Object diameters can be converted to km, object masses to kg, and vice versa.
Data is included for the sun, planets, Earths moon, and even Pluto.
A handy astronomy utility for public outreach or student use.