When using the Custom Design platform in JMP, after you define the factors in your design, you may specify the model terms of interest (for example main effects, interactions or power effects). Then, in the Design Generation dialog, the number of runs is suggested and calculated according to the specified model.
The minimum number of runs corresponds to a saturated design, which means there are as many runs as there are parameters to be estimated in the model with no degrees of freedom for error. Even though saturated designs can allow many factors to be studied with relatively few runs, because these designs give no information about the underlying variation a saturated design with the minimum number of runs is usually not advisable.
The Default number of runs provides a "recommended" number of runs that is greater than the minimum number, and will allow estimation of the effects entered in your model and the residual error.
[Previously JMP Note 48962]