Which element is most abundant in the universe?

Hydrogen is overwhelmingly the most abundant element in the universe, comprising approximately 75% of all baryonic (normal) matter by mass and about 92% by number of atoms. It was created in the first minutes after the Big Bang (Big Bang nucleosynthesis). Helium is the second most abundant at roughly 24% by mass. All other elements combined — carbon, oxygen, nitrogen, iron, etc. — make up less than 2% of the universe's normal matter. On Earth, the picture is very different: oxygen is the most abundant element in the crust (46% by mass), and iron dominates the core. The human body is about 60% hydrogen by atom count. Stars are essentially hydrogen factories, fusing it into heavier elements throughout their lifetimes.