We present a mathematical model to quantify parameters of mouse excisional wound healing from photographic data. The equation is a piecewise linear function in log scale that includes key parameters of initial wound radius (R ), an initial wound stasis phase (T ), and time to wound closure (T ); subsequently, these terms permit calculation of a latter active proliferative phase (T ), and the healing rate (HR) during this active phase. A daily photographic record of wound healing (utilizing 6 mm diameter splinted excisional wounds) permits the necessary sampling for robust parameter refinement. When implemented with an automated nonlinear fitting routine, the healing parameters are determined in an operator-independent (i.e., unbiased) manner. The model was evaluated using photographic data from a splinted excisional surgical procedure involving several different mouse cohorts. Model fitting demonstrates excellent coefficients of determination (R ) in each case. The model, thus, permits quantitation of key parameters of excisional wound healing, from initial wounding through to wound closure, from photographic data.