Justin Bieber on Wednesday announced his massive Purpose World Tour.

The 21-year-old will be hitting up 58 cities on the upcoming tour, which kicks off on March 9 in Seattle and wraps up July 18 at New York's Madison Square Garden, according to Rap-Up.

Bieber announced the tour during his recent appearance on "The Ellen DeGeneres Show." But during the announcement, the singer forgot the tour's launch date.

"It was the only thing I had to remember," Bieber said while on "Ellen," before asking for help from DeGeneres and people off-camera. "You can go to my website to find out. What am I doing? I'm here to promote an album and a tour and I'm not doing any of that right."

Stops on the singer's world tour are spread across North America and Canada, including dates in Vancouver, Las Vegas, Dallas, Atlanta, Chicago, Boston, and Miami, among others. There will also be two-night stints at Brooklyn's Barclays Center, Los Angeles' Staples Center, Chicago's Allstate Arena and Toronto's Air Canada Centre.

Before heading out on tour, Bieber is set to play two back-to-back shows at the Los Angeles Staples Center on Friday, Nov. 13 to celebrate the release of his upcoming album "Purpose."

Bieber last toured from September 2012 to December 2013 while on his Believe Tour.

For the Purpose World Tour, American Express card members have access to pre-sale tickets beginning on Nov. 16 at noon local time. Tickets for the public will be made available on Nov. 20 at 10 a.m. local time.

Bieber is set to release his fourth studio album, "Purpose," on Friday, Nov. 13. The album has already produced the singles "What Do You Mean?" and "Sorry." It is the follow-up to 2012's "Believe," which spawned the singles "Boyfriend," "As Long as You Love Me," "Beauty and a Beat," "Right Here" and "All Around the World."