The present study concentrates on the empirical formulas of Goda [1975, 2009]. The formulas were proposed for computing the transformation of three common representative wave heights (i.e. H 1/3, H max and H m0) on plane beaches. The objectives of the present study are to verify the Goda formulas for computing the transformation of H 1/3, H max and H m0 on unbarred beaches and to extend the formulas for computing the transformation of H m, H rms and H 1/10. Laboratory data from small-scale and large-scale wave flumes with unbarred beach conditions are used to verify the formulas. The verification shows that the formulas give very good predictions of H 1/3 and H m0, but give fair prediction of H max. The formulas are rewritten in the form of a general formula. The general form of Goda formulas is recalibrated and extended to compute other representative wave heights (i.e. H m, H rms and H 1/10). The general formula gives very good predictions of H m, H rms, H 1/3, H 1/10, H max and H m0.