The transverse rectus abdominis myocutaneous (TRAM) flap is commonly used in breast reconstruction surgery. However, one of the challenges of this method is intra-operative estimation of the volume of the pedicled flap. An accurate estimation will help in achieving a more symmetrical breast volume and therefore aesthetic results. Here, the authors report a simple, inexpensive and objective method of estimating the TRAM flap size intra-operatively. This method can be done using equipment readily available in most operating theaters. This particular method has been used in our unit which has led to more consistent results with better observed symmetry.