Similarities- They are both gas giants containing the same gasses such as Hydrogen and Helium. Jupiter and Saturn both have rings but Jupiters rings are very light. Jupiter and Saturn both have water in their clouds which is water vapor. They both orbit the sun.
Differences- Jupiter has a higher density rate than Saturn. Jupiter has 67 moons and Saturn has 62 moons. Saturn's color is yellow and orange, and Jupiter's colors are mostly red, white, and brown. Jupiter is a very hot planet, and Saturn is classified into a cold planet.