The winger, 25, joins the Toffees for the remainder of the season and is the club’s third signing of the January transfer window.
El Ghazi arrives to bolster Everton’s attacking options for the second half of the campaign.
He insists he is determined to ensure Rafa Benitez’s side finish “much higher up the table” than their current place of 15th.
El Ghazi told the club’s website: “I’m really excited. Everton is a big club, I cannot wait to get started.
“I want to show my quality to my teammates, to the Club and, of course, the fans. I want to put a smile on their faces.
“I’m ready and willing to work hard for it and for all of us to work together.
“I’ve met a few fans already and it’s great to see how people live for the Club. It’s basically their religion. You just want to give it your all and show them what you can do to make them happy.
“I just want to focus on working hard, getting into the team, fighting for my place and, with the boys, to get Everton where it belongs - that is much higher up the table. We have a really good squad.
“I can always score a goal in an important moment. I can add a lot of value with my pace and technique going forward. I can hold the ball and I am decent in one-on-ones. I am ready and can’t wait.
“If I can score goals like the one I scored against Everton, for Everton now, then I will be a happy man.”
Why has El Ghazi joined Everton?
El Ghazi scored 11 goals in 31 appearances for Villa last term after helping them to promotion from the Championship the previous year.
He fell down the pecking order this season, though, having played only 12 times in all competitions for the midlands outfit.
The Holland international gives Rafa Benitez another wide option as Everton aim to push up the Premier League table.
Summer signings Demarai Gray and Andros Townsend have been excellent additions, having scored six goals apiece this season.
Meanwhile, Anthony Gordon has also made hurtling progress and is now firmly established himself as a first-team player.
But El Ghazi will be another winger that Benitez can call upon in the second half of the campaign.
Eagled-eyed supporters had spotted that El Ghazi was following Everton’s Instagram account before his move was confirmed.
The only other club accounts he follows on the social media platform are Villa and former club Ajax.
It’s reported that Everton hold the the option to buy El Ghazi in the summer.
He will be available for the trip to Norwich City on Saturday.
El Ghazi represents the Blues’ third signing during January - after recruiting left-back Vitaliy Mykolenko and right-back Nathan Patterson from Dynamo Kiev and Rangers respectively.
Lucas Digne has gone the other way to El Ghazi, having sealed his move to Villa earlier today for a fee of around £25 million.