Since a proper listing of all modificiers related to a characters size isn't presented in the Core rulebook, I've compliiled a table here for easy reference. //relevant rules are listed in the PHB (pag. 179 a.o. ) and the Bestiary (pag. 292-297)297).// ^^ Size ^^ Str ^^ Dex ^^ Con ^^ Natural Armor ^^ AC/Attack ^^ CMB/CMD ^^ Fly ^^ Stealth || || Fine || same || +2 || same || same || +4 || -4 || +2 || +4 || || Diminutive || same-2 || +22 || same || same || +2 || -2 || +2 || +4 || || Tiny || -4 || +2 || same || same || +1 || -1 || +2 || +4 || || Small || -4 || +2 || -2 || same || +1 || -1 || +2 || +4 || || Medium || 100 || 100 || 100 || 0 || +0 || +0 || +0 || +0 || || Large || +8 || -2 || +4 || +2 || -1 || +1 || -2 || -4 || || Huge || +8 || -2 || +4 || +3 || -1 || +1 || -2 || -4 || || Gargantuan || +8 || same || +4 || +4 || -2 || +2 || -2 || -4 || || Colossal || +8 || same || +4 || +5 || -4 || +4 || -2 || -4 || The changes in the table listed above are additive, thus a character switching size from medium to huge would get the following total changes: +16 str, -4 Dex, +8 Con, +5 to Natural Armor, -2 to AC&Attack, +2 to CMB&CMD, -4 to Fly and -8 to stealth.