Abstract Log analysis without the aid of taped or digitized data, and a mini-computer, is a tedious chore. A typical desk top interpretation may consist of manual data extraction from log prints, hand plotting the appropriate crossplots for parameter selection, and then processing the data level by level in a hand held programmable calculator13. Fine tuning the calculations and documenting the results is very time consuming if the evaluation involves multiple zones and many levels. This paper presents a spreadsheet log analysis program for the purpose of organizing pertinent well information and log data, minimizing computation time, fine tuning results, and producing documentation. The program is very flexible, easy to use, and includes sophisticated techniques and industry standard logic. The program is open ended and is a suitable model for other similar applications. Well log data is processed over multiple runs and includes zoning of log parameters, water saturation, porosity, and shale models. Custom menu options are provided for easy use. The program requires a 640K personal computer and was developed in LOTUS 1-2-3* version 2.01.