Quantitative investigation of a standard test shim for magnetic particle testing has been carried out. The current values of the magnetizing yoke to obtain magnetic particle indication were measured experimentally. An analytical model for the experimental conditions was then formulated to obtain the amplitude of the leakage magnetic flux from an artificial groove in a type A standard test shim. The magnetic flux densities in the type A standard test shim and the test object were obtained using finite element analysis. In a test object with high permeability, the magnetic flux density was almost in the saturation regime when the magnetic particle indication was obtained. On the other hand, in a test object not having high permeability, the magnetic flux density was small when magnetic particle indication was obtained. © 2011 Elsevier Ltd. All rights reserved.