Which is/was largest animal ever lived on the earth (present or past) in terms of weight?

Answer 1

Balaenoptera Musculus - a Blue Whale

The largest animal ever known to exist is Balaenoptera musculus, commonly known as the blue whale. The blue whale is larger than any dinosaur discovered so far.

The largest blue whale to date is a female that weighed 194.88 US Ton / 389,760 pounds / 176,792 kg, where the largest known Dinousaur- Argentinosaurus, weighed only about 90 US Ton / 180,000 pounds.
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