Detailed sizes

[Brother Androx]

I found a post on DakkaDakka about the equivalent sizes of things like Rhinos, etc vs real world but it's a confusing TL:DR of 1/48 vs 28mm vs 1/32. 

Can someone set me in the right direction for finding true sizes of the vehicles in 40k.  I don't play so I don't know if these are covered on their respective codex or if it's just a guessing game.
No, I'm not building a full size predator, but it would be awesome.


Thanks for the help.

[MarcMiles]

Hindi ko alam kung gaano karaming mga pag-update ang ginawa upang hindi ako makatutulong sa pagrerekomenda sa kanila.