Altogether 2,292 people were killed by US missiles, including as many as 775 ordinary people, found a probe by the Bureau of Investigative Journalism.
The supposedly precision air strikes started under President George W Bush but have been stepped up since President Barack Obama came to power.
But they have left families in Pakistan in fear. In just one attack on a madrasah in 2006 up to 69 children died.
The figures will send shock-waves through Pakistan, where political and military leaders decry the strikes in public, but privately let the US carry on, said Chris Woods, who led the research.
"This is a military campaign run by a secret service which raised problems of accountability, transparency and you have a situation where neither the Pakistanis nor Americans are clear about any agreements in place and where the reporting is difficult," he told the Daily Telegraph.
Militants lived next door to Din Mohammad in Danda Darpakhel, North Waziristan. They were allegedly part of the Haqqani Network, a group fighting US forces in nearby Afghanistan.
In September 2010 CIA Reaper drones unleashed Hellfire missiles into the compound, killing six alleged militants. But one of the Hellfires missed its target, and hit Din Mohammad’s house instead. He survived. But his son, his two daughters and his nephew all died. His eldest son was a student at a Waziristan military cadet college. The other three children were all under school age.
While researchers from Bureau of Investigative Journalism’s field have confirmed the details of this strike, the US still denies that ordinary people are being killed and in seven of all US strikes may have killed children, according to the Pakistani Express Tribune.
Throughout the seven years of CIA strikes on Pakistan, the Bureau says it has found trustworthy reports of 168 children killed in attacks on tribal areas.
“Even one child death from drone missiles or suicide bombings is one child death too many,” said Unicef, the United Nations children’s agency.
Most children died in air strikes on Pakistan during the Bush presidency, when 112 children were reportedly killed. More than a third of all Bush drone strikes appear to have resulted in the deaths of children, the bureau said.
A US counter-terrorism official denied that civilians were now being killed and told the Express Tribune: “Nobody is arguing perfection over the life of the programme, but this remains the most precise system we’ve ever had in our arsenal.”