The coldest planet of solar system is:

There are eight planets in our Solar System.
Neptune is vary far away from Sun.
Neptune is also known as “Ice Giant”.
Average temperature of Neptune is -215C.
The distance of Neptune from Sun is 4.47 Billion Km.
Remember, the distance of Uranus is 2.94 Billion Km.
Venus is the hottest planet in solar system.
Its normal temperature is 470 Degree Celsius.