Hemophilia A (HA) is characterized by spontaneous bleeding and pain. To understand mechanisms underlying HA pain, we developed models of chronic´pain in FVIII knock-out (F8KO; B6;129S-F8tm1Kaz/J) male mice using innovative translatable measures to assess pain-related behaviors & gait. We tested for: [i] mechanical hyperalgesia using von-Frey monofilaments; [ii] physical activity using weight-bearing with incapacitance meter and video recordings of free moving mice for locomotion (walking/running), grooming (licking/rubbing body) & rearing (standing); and [iii] gait analysis during normal walking using in-house assembled MouseWalker with high-speed camera & artificial intelligence (AI)-based algorithms.