La Liga has better players than Bundesliga - Kroos
The Germany international moved to Spain in July despite being a first-team regular under Pep Guardiola at Bayern Munich last season.
Kroos was part of a side that won a league and cup double before helping Germany lift their fourth World Cup in Brazil in July.
Having settled in at Real, the 24-year-old has offered his thoughts on the differences between Spain's top flight and the competition he has left behind.
"There are differences," said Kroos. "The teams have quality just like in Germany, but they're a bit different.
"Teams in the table below still play beautiful football. The Spanish league has better footballers than the German league.
"However, in Germany there are more teams that are uncomfortable to play against because they are more aggressive than teams in Spain.
"From the level both leagues are equal. You'll win no game easily.
"It's always a lot of work. This is true in La Liga as well as in the Bundesliga. You must always give all you have."
Real started the campaign sluggishly but have gone on to win their last six matches in all competitions, their latest success a 5-0 victory over Athletic Bilbao on Sunday.