Wound Healing Calculator

This calculator estimates wound closure time from two independent factors: wound geometry and patient healing capacity. Wound Area is simply Length times Width, and Wound Volume multiplies that by Depth -- both grow directly with every dimension you enter. Healing time starts from a baseline tied to Wound Type -- 14 days for a clean surgical incision, 21 for a traumatic wound, 60 for a pressure ulcer, and 90 for a chronic ulcer -- because these categories differ in how much tissue damage and impaired circulation they typically involve, not just in size. That baseline is then extended: wounds larger than 4 cm² add 3 days per additional cm² of area, and wounds deeper than 1 cm add 7 days per additional cm of depth, reflecting the extra tissue volume that has to fill in through granulation. Patient factors apply as multipliers on top of the geometry-adjusted baseline -- age past 40 slows healing by roughly 1% per year past that threshold, diabetes multiplies the estimate by 1.5x, smoking by 1.3x, and poor nutrition by 1.4x, while good nutrition speeds healing by a modest 10%.

Weekly Area Reduction is derived from that same Estimated Healing Days figure -- it's the constant weekly percentage that would compound the wound down to about 5% of its original area (in practice, closed) right at the estimated healing time, so the two outputs never contradict each other. This also keeps the estimate consistent with the Sheehan et al. clinical finding that roughly 53% cumulative area reduction by week 4 predicts eventual healing: a wound this calculator estimates will close in a few weeks always clears that 53% mark comfortably by week 4, while a wound estimated to take many weeks reduces more gradually. Dressing frequency and the wound-contraction share of closure are set by wound type and depth, not by a separate formula. Treat every number here as a planning estimate, not a diagnosis -- actual healing depends on infection status, vascular supply, and wound-care technique that this tool does not measure.