How ThriftyRoo compares prices
ThriftyRoo uses current Amazon offer data and cached results no more than 24 hours old. Amazon remains the final source for price, availability, seller, and condition at checkout.
Used and open-box discounts
Used-mode results compare the lowest available used offer with the current new offer for the same product. Percentage discount sorting uses that difference; it does not treat a different model or package size as the new-price baseline.
Price-per-unit comparisons
Unit quantities come from seller metadata and may be incomplete. ThriftyRoo chooses the most common unit in the result set, safely converts compatible measurements to that basis, and sorts them by estimated price per unit. Relevant products with incompatible units remain visible in separately labeled groups.