The IBF champion Joshua tipped the scales at 17st 12lbs 2oz, 10 pounds heavier than Klitschko, ahead of the Wembley fight, live on Sky Sports Box Office, with the vacant WBA 'super' title also at stake.
Klitschko was greeted with boos when he made his entrance at Wembley Arena and the 41-year-old seemed to acknowledge the crowd by giving a peace sign after he weighed in at 17st 2lb 6oz.
Joshua followed Klitschko onto the stage, sparking roars of support from thousands of fans, and raised his fist in a triumphant gesture as the weight was announced.