PURPOSE: To investigate the influence of axial length on different ocular parameters and create a predictive tool for refractive error progression. METHODS: Two eye models were used to simulate refractive errors, namely the Liou-Brennan and the Goncharov-Dainty. Both models were simulated using Zemax OpticStudio. Simulations were made by varying axial length and central corneal radii of curvature, with values ranging from 21.5 to 28.5 mm and 7.0 to 8.5 mm, respectively. Additionally, simulations of different lens parameters were included. RESULTS: Refractive error maps were produced for different ethnicities and a comparison with experimental results was undertaken. These showed the relationships between axial length and crystalline lens thickness, refractive index and curvatures of the cornea and lens. CONCLUSIONS: The concept of refractive error maps may provide more insight into the refractive state of individuals and groups with provision for a comparative analysis. With further experimental data added, such refractive error maps could be used as a predictive tool.