How long was The Age of Dinosaurs (Mesozoic Era)?

The Age of Dinosaurs (Mesozoic Era) lasted 186,000,000 years (252,000,000 BC – 66,000,000 BC) across 3 major phases.

Duration Overview

Duration

186,000,000 years

Start

252,000,000 BC

End

66,000,000 BC

Triassic Period 51M years

252,000,000 BC – 201,000,000 BC

51 million years. First dinosaurs appear. Pangaea intact. Hot and dry.

Jurassic Period 56M years

201,000,000 BC – 145,000,000 BC

56 million years. Giant sauropods. Pangaea breaks apart. Lush vegetation.

Cretaceous Period 79M years

145,000,000 BC – 66,000,000 BC

79 million years. T. rex, Triceratops. Flowering plants. Ends with Chicxulub asteroid.

That's 186 million years — a span of deep geological time. Entire species evolved and went extinct within this period.

How long was The Age of Dinosaurs (Mesozoic Era)?

186 million years (252-66 million years ago). Divided into Triassic, Jurassic, and Cretaceous periods. Ended by asteroid impact.

When did The Age of Dinosaurs (Mesozoic Era) start and end?

The Age of Dinosaurs (Mesozoic Era) began in 252,000,000 BC and ended in 66,000,000 BC, spanning 186,000,000 years.