tl;dr:Speculative cost analysis of Amazon Prime Day 2023's AWS bill. The author calculates the on-demand cost at retail pricing for various AWS services used during the 48-hour event. The total estimated cost comes to $102,424,943.84. Even though this figure is likely much higher than the actual cost, considering the volume discounts and internal adjustments, the estimated infrastructure spend is a small fraction compared to the $12.7 billion in sales generated during Prime Day, highlighting the efficiency and return on investment of AWS services.