Humans have killed 2.9 million whales over the last century in what has been described as 'the largest hunt in human history'.
The figure is believed to be the first global estimate of the number of whales killed by industrial harvesting from twentieth-century hunting.
Scientists estimate that between 1900 and 1999, 276,442 whales were killed in the North Atlantic, 563,696 in the North Pacific and 2,053,956 in the Southern Hemisphere.
Robert Rocha, director of science at the New Bedford Whaling Museum in Massachusetts who led the research, said in terms of sheer biomass, whaling was the largest hunting activity of humans.
Rocha came up with the number with fellow researchers Phillip Clapham and Yulia Ivashchenko of the National Marine Fisheries Service in Seattle, Washington.
'Between 1990 and the middle of 1962, the same number of sperm whales had been killed by industrial methods as had been taken during the 18th and 19th centuries,' the researchers wrote.
'Astonishingly, this feat was then repeated between 1962 and 1972.'
'The total number of whales we killed is a really important number,' Stephen Palumbi, a marine ecologist at Stanford University in California told Nature.
The researchers arrived at the figure after conducting interviews with former Soviet whalers and researchers, and combining that information with reports from the whaling industry.
For hundreds of years people hunted whales for their oil to fuel lamps and candles, or for instance, to be used to lubricate machinery.
Today some areas kill whales to sell their meat for profit..
The new number could be 'an underestimate,' Dr Howard Rosenbaum, director of the Wildlife Conservation Society's Ocean Giants Program, told NBC News.
'The question is, given the state of today's oceans and the status of some whales, can depleted populations recover to their pre-whaling, historic levels?'
In the old days of whaling, sail ships and rowing boats were used to hunt whales with sailors chased the whales and threw harpoons at them.
During the late 1800s, steam powered ships replaced the old sailing boats, travelling all over the world and killing whales in vast numbers with exploding harpoons.
A 1986 moratorium on international whaling has led to a decrease in the number of whales killed, scientists say.
But current populations are now under threat from modern challenges such as military sonar, larger ships, and climate change.
Reports indicate that the number of sperm whales is down to one-third of their pre-whaling population, and that blue whales have been depleted by up to 90 per cent.
Some species have begun to recover, but others, such as the North Atlantic right whale, are now facing extinction.