Family historians can access a different collection on MyHeritage for free every day throughout June.
The website announced it is unlocking 2,043,456,361 records from 16 countries in total.
Today’s free collection is 48,076,879 Danish church records, dating from 1576 to 1919.
UK family historians will be particularly interested in free access to the 1939 Register of England & Wales on 22 June.
The Register was compiled on 29 September 1939 to record the civilian population of England and Wales at the outbreak of the Second World War.
It is the most recent significant census substitute available, and is usually only available behind a paywall on MyHeritage, Ancestry and Findmypast.
MyHeritage is also offering free access to collections from Sweden, Norway, Finland, the USA, Canada, France, the Netherlands, Hungary, Spain, Australia, Brazil, Greece and Germany.
From 7 to 11 June, it is offering access to millions of American records including city directories, Social Security applications and claims, historic newspapers, Ellis Island passenger lists and the 1940 census.
Other notable collections include an exclusive collection of over six million Canadian newspapers on 15 June; over 16 million Australian electoral rolls on 25 June; and over 200,000 Mandatory Palestine naturalisation applications on 26 June.