Net price calculators (NPCs) are online tools designed to increase transparency in college pricing by presenting students with individualized estimates of net prices to attend a given postsecondary institution. The federal template NPC predicts identical aid awards for similarly profiled students attending the same institution. Using the 2012 National Postsecondary Student Aid Survey, we use regression analysis to assess variation in actual financial aid awards among students predicted by the federal template NPC to receive identical awards. We find estimated aid, derived from the federal template NPC, accounts for 70 percent of the variation in actual grant aid received by students. We then consider modifications to the federal template NPC that include an additional upper-income bracket option and indicators of both high school grade point average and Free Application for Federal Student Aid filing time. These modifications explain an additional 16 percentage points, or more than half, of the unexplained variation in actual grant aid awards across all institutional sectors. These findings are especially relevant as legislators consider policy efforts to bring greater transparency to college cost and pricing, including creating a universal NPC in which prospective students can enter information once to receive net price estimates at any institution.