What colour is Jupiter?
Short answer: Yellow-orange.
Long answer: Jupiter is a gas giant planet so there is no "surface" to look at. When you look at Jupiter, you're seeing the gases in its atmosphere.
Jupiter has weather bands that wrap around the planet in stripes parallel to its equator. These bands are various colours including red, orange, brown, yellow and white. Jupiter has a very active atmosphere and the weather bands are constantly moving and changing.
The colours of Jupiter are created by chemical elements in its atmosphere interacting with and reflecting light from the Sun. Although Jupiter is made largely of hydrogen and helium, there are plenty of other elements and compounds to create different colours, including phosphorus, sulfur, hydrocarbons and ammonia crystals.
Seen from Earth with the unaided eye, Jupiter is white. It looks like a bright white star. With a good backyard telescope you can see some colour in the weather bands but it usually still looks mostly white.
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