How old is the Earth?

The age of the Earth is estimated to be about 4.54 billion years.

This figure is not based on guesswork. Scientists calculate it using a precise method called radiometric dating, which measures the decay of radioactive elements in rocks and meteorites. Since the oldest Earth rocks are constantly recycled due to geological activity, researchers often study ancient meteorites, which formed around the same time as the solar system.

Multiple independent studies over decades have consistently produced the same estimate, making it one of the most reliable scientific measurements.

To put this into perspective:

• If Earth’s history were compressed into a single year
• Humans would appear only in the last few minutes of December 31

Why this matters: Knowing Earth’s age helps scientists understand the timeline of continental formation, evolution of life, and major geological events.