An updated tabulation is presented of the optical properties of intrinsic silicon, of particular interest in solar cell calculations. Improved values of absorption coefficient, refractive index and extinction coefficient at 300 K are tabulated over the 0.25–1.45 μm wavelength range at 0.01 μm intervals. The self-consistent tabulation was derived from Kramers–Kronig analysis of updated reflectance data deduced from the literature. The inclusion of normalised temperature coefficients allows extrapolation over a wide temperature range, with accuracy similar to that of available experimental data demonstrated over the −24 °C to 200 °C range.