The average temperature of the Earth year round is around 61°F (16.1°C). The average coldest temperature on the Earth, in Antarctica, is around -60°F (-51.1°C) and the average of the hottest part of the Earth, in the Sahara Desert, is around 130°F (54.4°C).
The hottest temperature ever recorded on Earth was 136°F (57.77 °C) in El Azizia, Libya on the edge of the Sahara Desert. The second hottest, 134°F (56.6°C), was recorded in Death Valley, California in the Mojave Desert way back in 1913.
The coldest temperature on the Earth was recorded at Vostok, Antarctica on July 31, 1983 at -128.6°F (-89.22°C).