How big is an spinosaurus compared to a human?

Spinosaurus was 49 feet long, making it slightly longer than 8 average American men laying on their backs, each with his head under the other's feet.

As for its height, Spinosaurus's legs are not fully known, but from reconstructions, one would guess that the height to the top of a Spinosaurus's head, 12 feet, was just more than twice that of the height of a man. In addition, the sail on a Spinosaurus went up an additional 4.5 feet, approximately, making the distance to the highest point on a Spinosaurus three times that of a man's height.

Spinosaurus is known only from incomplete skeletal remains, so determining its weight is difficult. Estimates range from 4.4 tons, or 55 times that of a healthy average man, up to 10 tons, or 125 times the weight of a man, all the way up to 18 tons, or 225 times the weight of a man.