Blue whales are typically around 24–27 meters (80–90 feet) long as adults, with the very largest individuals reaching about 30 meters (98–100 feet) in length.

Quick Scoop

  • Most adult blue whales: about 80–90 feet long.
  • Maximum confirmed length: just under 100 feet (about 30 meters), with some historical reports very slightly above that.
  • Southern Hemisphere blue whales tend to be larger (often 90–100 feet) than those in the Northern Hemisphere (around 75–80 feet).

A simple way to picture it

If you lined up a blue whale next to familiar things:

  • It can be roughly as long as a basketball court (about 94 feet).
  • A very large individual can be close to the length of a small airliner, like a Boeing 737 (around 100+ feet).

In other words, when you ask “how long are blue whales,” you’re talking about an animal usually the length of a small building or sports court, and the largest ever reliably measured reached almost 30 meters from nose to tail.

TL;DR: Most blue whales are around 80–90 feet long, and the biggest reliably measured individuals are close to 100 feet (about 30 meters).

Information gathered from public forums or data available on the internet and portrayed here.