Britannica Sources used in this answer

How large is the observable universe in light-years?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

The observable universe is approximately 93 billion light-years in diameter.1

While the universe is 13.8 billion years old, the observable region is significantly larger than 27.6 billion light-years in diameter due to the expansion of space since the big bang. Objects that emitted light 13.8 billion years ago are now approximately 46 billion light-years away from Earth, making the total diameter of the observable bubble about 93 billion light-years. This region continues to expand as light from more distant objects reaches Earth over time.1