Hydrogen–sulphur flame analysis is conducted from a numerical database of planar and unstrained laminar premixed flames. Simulations are performed using a fully detailed chemical scheme of H2S combustion. Both the equivalence ratio of the mixture and the amount of oxygen contained in the oxidizer are varied. From the results, the behavior of the burning flame speed versus equivalence ratio and oxygen level is collected, major species concentrations are also reported together with intermediate species like SO, H2 and HSO. In the case of H2S rich mixture, the development of a post-flame region, where H2S reacts with SO2 to form S2, is recovered and the equivalence ratio at which it starts to appear is found to depend on the oxygen level in oxidizer. From the information gained with the detailed chemical kinetics, an automated method is proposed to generate a single-step kinetics that reproduces the response of the burning rate versus equivalence ratio and oxygen enrichment.