Numerous computer programs and calculations exist to predict the type(s) and severity of scale deposition, This paper compares scale index calculations, two scaling indices computing programs, and two computer predictive models on two wells with the actual field experience. The computer programs’ advantages and disadvantages are considered along with their accuracy in predicting field scale problems. The programs reviewed by this paper are tools to be used in conjunction with personal experience of water chemistry, field conditions, a program’s reproducibility, and one’s confidence level deposition, severity, and treating regimes. Kevwords: saturation indices, saturation levels, scale modelling, in the program to define and predict scale scale prediction, single point analysis