This chart shows the "depth" of various solar system gravity wells.
Each well is scaled such that rising out of a physical well of that depth in constant earth surface gravity would take the same energy as escaping from that planet's gravity in reality.
Each planet is show cut in half at the bottom of its well, with the depth of the well measured down to the planet's flat surface.
The planet sizes are to the same scale as the wells. Interplanetery distances are not to scale.
xkcd - A webcomic of romance, sarcasm, math, and language - By Randall Munroe