Blow forming is a commonly used production method to deform superplastic sheets. Several papers have appeared to analytically predict the pressurization sequence needed to control the inflation process at a desired strain rate. Some of them, however, are based on an over‐simplified assumption of uniform thickness reduction during the inflation, which often leads to non‐conservative prediction of pressure‐time path. Others have been more rigorous in the formulation, which on the other hand, results in more extensive equations requiring iterative method with a computer program. This paper presents a modified approach. Ignoring the assumption of uniform thinning, a set of physically sound yet easy‐to‐use equations for obtaining pressure‐time curves, heights of the deforming dome, and thickness variations both in space and time, are derived. The analytical results compare favorably with the experimental data and more elaborate finite element solutions.