What do you imagine be the height of skele boys? I often see people headcanoning Sanses as either really short (around 5") like in game or taller, often followed by statement that all monsters are taller than most humans.
Let me start by saying that I know you asked this question in a previous ask along side another one, this one seemed a little easier to answer at the moment though so I did it first. I'll try and get to the other ask asap though! ♡♡♡♡ Thank you for continuing to send asks even when I'm so slow to answer them!!
I try not to have specific heights in mind for the boys so that anyone of any height isn't left out when trying to self insert, but usually a Sans will be shorter than the reader, reaching about collarbone height, while the reader will only reach mid to low rib for Papyrus. I do have a few exceptions for that, such as the horror boys and the outer boys since special circumstances apply to them. I do headcanon that most monsters are pretty large, but Sans always just feels so small to me haha. I'll line them up for you from tallest to shortest though so you can put yourself on the list wherever you want, and if you want a taller or shorter version for any future asks, just feel free to include that in any asks.
Spindle (Undertomb Papyrus) who is the tallest from all of the corrupted human magic he absorbed from eating so many of them.
Oberon (Outertale Papyrus) who is very tall because it's common for things in space to be larger. I think I read somewhere that astronauts come back from space with an extra inch or two! But I'd fact check that.
Chewy (Horrortale Papyrus) who is also tall from consuming large quantities of human magic, but is shorter than Spindle because it wasn't corrupted magic.
Rust (Fellswap/Swapfell Red Papyrus)
Marmalade (Underswap Papyrus) and Syrup (Swapfell Purple Papyrus) are the same height and both are prone to slouching a lot.
Papaya (Undertale Papyrus)
Coffee (Swapfell Gold Papyrus) who is the shortest and youngest of the Papyri.
Pit (Undertomb Sans) who is the tallest Sans and is tall because like his brother, he absorbed a lot of corrupted human magic when he ate them.
Cosmo (Outertale Sans) who is tall like his brother because things tend to be larger in space.
Fell (Underfell Sans)
Wine (Swapfell Gold Sans) he wears heels, but he's still naturally taller than most of the other Sans.
Tale (Undertale Sans)
Berry (Swapfell Purple Sans), Razz (Fellswap/Swapfell Red Sans), and Blue (Underswap Sans) are all the same height. Berry and Blue wear regular flat boots whereas Rass wears a pair of toothpick heeled boots to make himself seem taller.
Butcher (Horrortale Sans) is the shortest Sans because he used all of his magic to keep himself alive without eating anything for a long period of time, and never ate human flesh like his brother so he had no extra magic to absorb causing him to shrink in size.