10 Amazing Facts About Killer Whales

9. Their length and weight

As babies, they weigh around 400 pounds or 181 kilograms, and measure between six and nine feet or 1.8 to 2.7 meters long. But that’s nothing compared to when an orca reaches adulthood. By that time, they can weigh up to six tons and be anywhere from 23 to 29 feet or seven to 8.8 meters long. They’re also one of the fastest animals in the world. When swimming, they can reach speeds between 30 and 40 miles per hour or 48 to 64 kilometers per hour.