Hey everyone, I was wondering how much someone like, oh I dont know...MEGATRON weighs? In particular the G1 cartoon when he is 6 meters and in IDW when he is 38 feet.

Depends on how you are doing scale. If Megatron becomes a tank, then probably between 30 and 60 tonnes. For comparison, an average Peterbilt semi-trailer tractor (the part that pulls the load) is between 17k lbs. (8.5 tonnes) and 65k lbs (30 tonnes), and a T-Rex weighs at most 31k lbs. (15 tonnes), so Megs would be between three to eight times the weight of Optimus, Magnus, and Grimlock. Even Starscream, as a jet, weighs in around 45k lbs.

Well I want the weight based on the height of each version, so if Megatron was 38 feet he would weigh more than if he were 19 feet or 6 meters. I am not confusing anything lol mainly I just want an estimated weight of the robot mode of each based off of the only information we have on their size.

Weight is the affect of gravity on an object, and that can vary based on gravity and mass. Because we don’t know what most Transformers are mad of there’s no way we can determine their mass. We could use the real world objects that they turn into as a frame of reference, but I think it’s a safe bet that Megatron as a tank still retains his Cybertronian armor, and it’s possible he could weigh much more that a real tank.

Remember also two objects of the same height can have different weights. In people for example, you can have two fellows who are the same height and weigh much different (like MJ and Charles Barkley, who are both 6’6”, but almost forty lbs apart).

Mass shifting = weight shifting, shown in the cartoon anytime someone picks up Soundwave (and his stored Menacing Menagerie). Without it, that little box would weigh TONS.

Weight for characters varies by continuity. Megatron is probably comparable to Optimus Prime in terms of stats. Optimus Prime is 22 tons in IDW. According to the Masterpiece Convoy review I found on BWTF.com Optimus has a weight of 28 tons. According to Japanese G2 comics, Optimus' Laser Rod body is 13.5 tons. Here's a rough compilation of TF stats including character weights: User:Iustitia - Transformers Wiki