Abstract Two miniature single sheet testers (SSTs), for measuring the magnetic properties of electrical steel sheet, have been built and calibrated. Small samples with dimensions 30×5 mm or 60×20 mm can be characterized. The calibration procedure is outlined and the magnetic path lengths for different yoke constructions are determined. The usefulness of the presented small size SSTs for magnetic characterization (power losses, BH-loops, permeability) is discussed. It is shown that these miniature SSTs are accurate in predicting magnetic properties on small samples and can be used in situations where large Epstein strips or conventional single sheets are not available.