What Is the Most Abundant Element on Earth?

While hydrogen is indeed the most abundant element in the universe, the story is quite different on Earth.

Here, gravity and the nature of Earth’s formation have led to a unique distribution of elements, making iron and oxygen the most abundant.

Iron Dominates Earth's Core

If we could sort and weigh all the elements across the entire planet, iron would account for over 32% of Earth’s mass.

According to World Economic Forum, iron, along with other heavy elements, sank to the center during Earth's formation, driven by gravitational forces that pulled the densest materials toward the core.

Oxygen: Abundant in the Crust

Oxygen comes in second, making up around 30% of the Earth as a whole.

However, it dominates the Earth's crust, accounting for 46% of its mass, primarily bonded in compounds with silicon to form silicates, the main components of rocks.

Silicon follows oxygen in abundance in the crust, making up about 28% of its composition.

Though hydrogen is the most common element in the universe (around 75% of the universe’s mass), it is rare on Earth, making up only 0.14% of the crust.

Much of Earth’s hydrogen escaped into space early on, but some remained bonded with oxygen to form water, essential for life.

Earth's Elemental Distribution

Here’s a quick look at the most common elements based on Earth's total mass:

1. Iron – 32.1%

2. Oxygen – 30.1%

3. Silicon – 15.1%

4. Magnesium – 13.9%

5. Sulfur – 1.9%

And in the crust:

1. Oxygen – 46%

2. Silicon – 28%

3. Aluminum – 8.3%

4. Iron – 5.6%

5. Calcium – 4.2%

The fascinating distribution of elements in Earth is largely thanks to the intense heat and collisions that shaped our planet 4.6 billion years ago, causing heavier elements to sink and lighter ones to rise.

While hydrogen might reign in the cosmos, Earth’s composition is defined by elements like iron and oxygen, which create the structures we stand on every day.