Marvel's like Captain America and Iron Man have limits to their strength, the Hulk certainly has some as well. A deep dive into the comics reveals the precise amount of tons the Hulk can lift before he cannot lift anymore...but Hulk has a secret to his strength that other superheroes cannot hope to match.
Complicating matters regarding a precise measurement of the Hulk's strength is the fact that Bruce has numerous alter egos, each of which could be considered a "true" Hulk. The so-called Savage Hulk is the most famous; with the mind of a child but the strength to lift cars with ease, his is the Hulk with the well-known "Hulk Smash" limited vocabulary. Other incarnations include Joe Fixit (a tough-as-nails Mafiosi who enjoys the nightlife), the Green Scar (a rage-filled but intelligent Hulk who crashed on the planet Sakaar), and the Immortal Hulk (a truly dangerous horror-themed Hulk who can never actually die).
The Hulk can easily lift people, vehicles, and even buildings, but a quantified calculation of sheer strength appears only 25 years into the Hulk's own history. In the fourth issue of 1984's Secret Wars, the Hulk and a group of heroes are trapped under a mountain by the Molecule Man and Hulk is the only one who can save them from certain death. The cover of the issue asserts that the mountain weighs over 150 billion tons - and the Hulk lifts it all for an extended period of time (thanks to the heroes making Hulk angry enough; his strength is directly proportional to his level of anger). Even taking into this tremendous weight, it's not even the maximum strength that the Hulk has displayed.
The Hulk Can Break The World
In Infinity #6, the Hulk s the entire weight of a star with his strength alone. If the star's weight was equivalent to the weight of Sol, the Hulk is capable of lifting 2 octillion tons. These numbers are far beyond human comprehension, and the laws of physics as humanity understands them simply do not apply to the Hulk; lifting a mountain is a trivial matter. The World War Hulk series (occurring after Planet Hulk) revealed the Hulk is capable of creating earthquakes simply by stomping, and the Immortal Hulk can even destroy planets (under certain specific conditions), but considering the above feat of holding a star, this is hardly surprising.
It is almost a certainty that Stan Lee and Jack Kirby did not imagine a star-lifting Hulk when the character was first created in 1962 (his mightiest feat in his debut issue as the Grey Hulk was smashing the hood of a Jeep). It is a natural occurrence for writers to increase the abilities of their respective superheroes as time es, but the Hulk is a special case. It took over 60 years, but the Incredible Hulk went from lifting a car to a star - and his hard limit has yet to be found.
