Largest pterosaurs:
Santanadactylus araripensis 5.7 m (19 ft)
Cearadactylus atrox 5.5 m (18 ft)
Caulkicephalus trimicrodon 5 m (16 ft)
Istiodactylus latidens 5 m (16 ft)
Lacusovagus magnificens 5 m (16 ft)
Liaoningopterus gui 5 m (16 ft)
Phosphatodraco mauritanicus 5 m (16 ft)
Anhanguera sp. 4.5 m (15 ft)
Proof that I actually found this, google search: List of biggest pterosaur