Harry Kane opened the scoring in the eighth minute. England led 4-0 before half-time, after further goals from Jude Bellingham, Anthony Gordon and Bukayo Saka.
Kane and Saka both scored two goals in the match after further goals in the second half.
In the final stages, substitute Morgan Rogers, who had come on just over 15 minutes earlier, also made it 7-0.
Croatia coach Slaven Bilic took over the national team after the World Cup. Since then, there has been one win (2-1 against the Czech Republic) and two losses (1-4 against Spain and 0-7 against England).
On Tuesday, the Croatians will have a chance for revenge when they face Spain again in the final match of the national team camp.

