City Hall analysts said publicly listed house builders have made pre-tax profits of £30bn over the last decade.
Khan is proposing a 10% levy paid over ten years to raise £3bn to carry out remediation work needed after the Grenfell fire.
City Hall said the staged payments would reduce the typical profit margin developers make on new homes from 20 to 18.7 % which it said was “a very small contribution for the enormous impact remediation works would have on people’s safety and quality of life.”
Khan said: “I have always been clear that the responsibility for funding building safety work must lie with Government.
“However, we cannot deny the role that industry has played in making decisions that have compromised the safety of buildings.
“I am determined to find a solution that can make homes safe without passing on the burden of the cost to leaseholders – it is wrong for them to bear the costs of historic errors they have played no part in causing.
“This levy would have a minimal impact on developer profits but would prove life changing for London leaseholders.”