An application software program intended to be used for estimation of the quantity of external blood loss during a surgical procedure by analysis of images of blood-laden absorptive devices (e.g., swabs) and suction canisters. It is intended to run on an off-the-shelf or dedicated portable computerized device (e.g., smartphone, tablet, laptop) which may require an Internet connection. It does not store any patient demographic or clinical data. It typically includes upgrades to the software.