What diameter is Betelgeuse?

Betelgeuse, a red supergiant star in the constellation Orion, has an approximate diameter of about 1,000 times that of the Sun, which translates to roughly 1.4 billion kilometers (or about 870 million miles). This immense size makes it one of the largest stars visible to the naked eye. Its actual size can vary due to pulsations, as it is a variable star.