Speaking during a World Cup media debriefing here Monday, Blatter revealed the body had used social media to gauge the tournament's success, reports Xinhua.
"We have improved on four years ago in South Africa," Blatter said.
"We consulted all our computers and our Facebooks and decided on 9.25 out of 10 because perfection does not exist in football.
"This was my 10th World Cup and my fifth as president and what makes this so very, very special was the quality of the football and the intensity of the games.AAThere was not one single match which didn't have this intensity. It's more than emotion and passion - it is a drama."
Blatter admitted that more needed to be done to combat prejudice at the 2018 World Cup in Russia.
According to media reports, some fans suffered from racism and homophobic slurs. The incidents came despite a pledge by Brazil President Dilma Rousseff before the tournament to make the anti-racism message a theme of the tournament.
"I am not at all happy with the way we fought against racism," the supremo said.
Blatter also said he had been surprised by the decision to award Lionel Messi the Golden Ball for the tournament's best player.
The Argentina forward scored four goals - all during the group phase.
"I was a little bit surprised when I saw Messi coming up to collect (the trophy for) the best player of the competition," Blatter said.
Earlier Argentina legend Diego Maradona described the decision as a "marketing" move.
The 53-year-old, who won the award after leading Argentina to World Cup glory in 1986, said Colombia's James Rodriguez deserved the accolade.