The growth of variable-rate technology (VRT) has led to site-specific management (SSM) of farm inputs. While fertilization was one of the first areas where VRT was implemented many producers do not have the ability to evaluate its performance. The objective of this study was to develop and validate a methodology to generate as-applied maps representing the fertilizer distribution from VRT applicators. An as-applied spatial data model was developed which merged pan test distribution pattern data and field application files (FAF) generated by VRT field control software to generate "as-applied surfaces." Collected field data was collected for model validation indicating good correlations for one applicator (several R2 > 0.70) with moderate success for another one (0.59 < R2 < 0.66). However, the correlation between the actual applied material and prescription maps (0.24 < R2 < 0.81) indicated a wide range for VRT performance from field-to-field. These results suggest the model output can be used to evaluate VRT performance and to compare variable-rate management approaches but also indicate the need for a standard VRT testing and evaluation protocol.