The Sun is about 1.39 million kilometers (approximately 864,000 miles) in diameter, making it roughly 109 times wider than Earth

. Its radius is about 696,000 kilometers (432,450 miles)

. The Sun is so large that around 1.3 million Earths could fit inside it

. In terms of mass, the Sun is about 333,000 times as massive as Earth and contains about 99.86% of the total mass of the entire Solar System

. Despite its immense size within our solar system, the Sun is considered an average-sized star compared to others in the universe, with many stars being significantly larger

. The Sun is nearly a perfect sphere, with its equatorial and polar diameters differing by only about 10 kilometers (6.2 miles)

. Measuring the Sun's exact size is complex, but recent studies using helioseismology techniques have refined its radius measurement to be slightly smaller than previously thought, by a few hundredths of a percent

. In summary, the Sun's diameter is about 1.39 million kilometers, making it the largest object in our solar system and vastly larger than Earth, but average compared to many other stars in the galaxy.