Transformers: Age of Extinction, the fourth in the series of films about form-changing Autobot robots that save the planet, powered up with $100 million US in Canadian and American box office sales, jump-starting a sleepy summer with the year's biggest opening weekend for a Hollywood movie.

22 Jump Street, starring Channing Tatum and Jonah Hill, was second with $15.4 million US in its third week in theatres, according to studio estimates. Animated film How to Train Your Dragon 2 took the No. 3 spot with sales of $13.1 million for the Friday through Sunday period at Canadian and U.S. cinemas. 

Transformers: Age of Extinction stars Mark Wahlberg in his first outing taking on the evil Dinobots. The series' three previous instalments, starring Shia LeBeouf, generated nearly $2.7 billion US in worldwide sales, according to Box Office Mojo.

The film took in more than $200 million overseas. Transformers added another $10.7 million on domestic IMAX screens and $16.6 million internationally.

Made for more than $200 million, the film pits Optimus Prime, Bumblebee and other Autobots against new villains. It met industry projections for its opening weekend.

The nearly three-hour movie garnered mostly poor reviews, with only 17 percent of 121 critics giving it a "fresh" rating, according to the site Rotten Tomatoes, but ticket buyers gave the film an A- rating according to polling service CinemaScore.

Prior to the opening of Transformers, summer movie ticket sales had lagged last year by 15 per cent, according to the box office tracking site Rentrak.