I'm very eh on this.
I say we should use Word OF God unless they either contradict the source material or Word Of God is not fully reliable (Murata)
Let's see. Beefcake is depicted as several 100 meters tall in those shots where you can see Fukegou and Saitama, which makes sense because if he were any larger they would be a pixel or two tall and not visible. You'll see that when you look at
these panels here. But when Beefcake is compared to the landscape, he's shown to be much, much larger. Buildings reach up to his ankles or knees, he towers over clouds and mountains. Let's go through the landscape depictions
Depiction 1, towering over mountains:
7133 meters
Depiction 2, towering over mountains again as he moves past hunters:
1200 meters~, mountains around waist height
Depiction 3, streaming towards city and towering over clouds:
2000-3000 meters
Depiction 4, wading through buildings with a 10-20 story building up to his knees:
500-600 meters
Depiction 5, swiping away city with fist larger than multiple story buildings:
900-1000 meters
Depiction 6, aftermath of city swipe towering over buildings:
233 meters
Depiction 7, taller than mountains when Saitama and his brother are on the shoulders:
1200 meters~ again
Depiction 8, standing over crater:
1013 meters
Depiction 9, crater shot 2, buildings not quite up to his ankles:
1000 meters
Depiction 10, Saitama flies towards him: while a 7 story building is around his ankles:
500-600 meters
Depiction 11, Beefcake falls on the city, dwarfing taller buildings by his calves:
1000 meter~