Scroll compressors are positive displacement machines of orbital motion that compress a gas by means of two interfitting spiral-shaped scroll members. Gas leakage is an important source of inefficiency in scroll compressors and it therefore needs to be estimated. Currently, correlations for leakage required in simulation models are based on simplified flow conditions. Thus, a high degree of uncertainty is associated with leakage predictions for the wide range of operating conditions found in actual applications. This paper reports a numerical analysis of radial and tangential leakage in scroll compressors considering different gases, operating conditions and geometries expressed as dimensionless parameters. Numerical models were developed to analyze the aforementioned phenomena in detail, including the geometry of the wraps. Based on the predicted values, correlations for the radial and tangential leakage of gas particularly suitable for comprehensive simulation models were developed and validated through comparison with experimental data and other models available in the literature.