LOS ANGELES — It wasn’t exactly a mighty victory, but “Jack the Giant Slayer” won the weekend at the box office.

The Warner Bros. 3-D action extravaganza, based on the Jack and the Beanstalk legend, made just $28 million to debut at No. 1, according to Sunday studio estimates. It had a reported budget of just under $200 million. “Jack” comes from Bryan Singer, director of the first two “X-Men” movies.

But the studio also hit a milestone with “The Hobbit: An Unexpected Journey” crossing the $1 billion mark worldwide. The first of three films based on the classic J.R.R. Tolkien novel has made $301.1 million domestically and $700 million internationally.

Estimated weekend sales:

1. “Jack the Giant Slayer,” $28 million

2. “Identity Thief,” $9.7 million

3. “21 & Over,” $9 million

4. “The Last Exorcism Part II,” $8 million

5. “Snitch,” $7.7 million

6. “Escape From Planet Earth,” $6.7 million

7. “Safe Haven,” $6.3 million

8. “Silver Linings Playbook,” $5.9 million

9. “A Good Day to Die Hard,” $4.5 million

10. “Dark Skies,” $3.6 million.