When pets are created, their height depends on their species, with some Neopets a lot larger than others. Here's a list of median heights, and a scale so you can see just how huge Eyries are compared to Flotsams.

Acara 41 cmGnorbu 42 cmKyrii 32 cmScorchio 120 cm
Aisha 40 cmGrarrl 100 cmLenny 60 cmShoyru 61 cm
Blumaroo 100 cmGrundo 41 cmLupe 60 cmSkeith 89 cm
Bori 40 cmHissi 44 cmLutari 57 cmTecho 61 cm
Bruce 80 cmIxi 61 cmMeerca 79 cmTonu 71 cm
Buzz 22 cmJetsam 25 cmMoehog 97 cmTuskaninny 51 cm
Chia 60 cmJubJub 40 cmMynci 80 cmUni 120 cm
Chomby 75 cmKacheek 31 cmNimmo 81 cmUsul 75 cm
Cybunny 32 cmKau 60 cmOgrin 70 cmWocky 51 cm
Draik 55 cmKiko 61 cmPeophin 41 cmXweetok24 cm
Elephante 41 cmKoi 36 cmPoogle 44 cmYurble 37 cm
Eyrie 160 cmKorbat 70 cmPteri 42 cmZafara 41 cm
Flotsam 21 cmKougra 65 cmQuiggle 31 cm
Gelert 60 cmKrawk 67 cmRuki 58 cm

FlotsamBuzzXweetokJetsamKacheekQuiggleCybunnyKyriiKoiYurbleJubJubAishaBoriAcaraPeophinZafaraGrundoElephantePteriGnorbuHissiPoogleTuskaninnyWockyDraikLutariRukiGelertKauLennyChiaLupeKikoShoyruTechoIxiKougraKrawkKorbatOgrinTonuUsulChombyMeercaBruceMynciNimmoSkeithMoehogBlumarooGrarrlUniScorchioEyrie