
The transportation records date from 1788 to 1868 and include all but a few thousand of the 163,021 convicts who were sent to Australia.
Information contained in the records includes name, date and place of conviction, length of sentence, name of ship, departure date and the colony to which they were sent.
Additional information in some cases includes occupation, marital status, religion and the date on which freedom was finally granted.
Josh Hanna, a spokesman for Ancestry.co.uk, estimated that more than two million Britons are directly descended from the deportees, meaning that there is a one in 30 chance of Britons having a convict ancestor listed among the records.
"These records are of significance not only to the one in four Australians who are of convict descent, but to the estimated two million Brits, many of whom are unaware of their links to the other side of the globe and who can now claim Australian convicts among their ancestors," he said.
Only two per cent of those deported were convicted of what are now deemed serious crimes such as murder or assault. Most had committed offences such as burglary or theft.
"While Australia's convict history has been well documented, there are thousands of individual stories in the collection just waiting to be told," said Hanna.