The present invention is a calibration and measurement system designed primarily for use in the rapid evaluation and characterization of open or visible wounds in patients. The invention in a preferred embodiment comprises a set of colored concentric rings, constructed of paper or synthetic material. The practitioner removes only as many rings, from the center outward, until the entire wound is visible within the open aperture at the center of the remaining rings. The area dimensions of the wound are then read out from the size of the inner remaining ring. Photography optionally records the wound appearance and size. A related system is developed for linear dimensioning of wounds. This invention is also designed to standardize the color scheme for accurate photography wound description. This color scheme is also applicable to a linear device to accurately describe wound size. The invention is also useful in forensic and accident investigations.