The biggest audience of the tournament so far was for England's win over Sweden.
There were two million streams of the win across the two websites and apps.
The quarter-finals against Spain had a peak TV audience of 7.6 million and a further 1.5 million streams.
France or Germany will face off in the final.
The semi-final will be shown on Wednesday on both the website and app.
The peak TV audience for women's football in the UK was over 12 million for England's World Cup semi-final loss to the US.
The crowd at Tuesday's game was a record for a European Women's Championship semi- final.
The previous record for the number of fans at a Women's Euros was set in the group stage.
There are no tickets left for the showpiece at Wembley.