How many kilometers is the earth from the sun?
149 Million km.
The average distance from the Sun to the Earth is about 149 Million km, average because the orbit of Earth is no a perfect sphere but an Ellipse. So sometimes the Earth is closer to the Sun and some times it is further away. When Earth is closer to the Sun it's called perihelion. At perihelion, the distance between the Earth and the Sun is about 146 Million km.
When the Earth is further away from the Sun, its called aphelion. At aphelion the distance between Earth and the Sun is about 152 Million km.
The average distance between the Earth and the Sun is referred to as 1 Astronomical Unit or 1 A.U .