Overview

Amazon calculates FBA fees based on the weight and dimensions of your item package — not just the product itself. Understanding exactly how Amazon measures these packages is essential for sellers who want to avoid unexpected fee increases and ensure they're being charged correctly. This guide breaks down the measurement process, which fees are affected, and how to request corrections when mistakes occur.

Key Points / What Sellers Need to Know

• Item package is not the same as the item — Amazon distinguishes between the standalone product, the individually packaged unit (item package), and the bulk shipping case. FBA fees are calculated using the item package measurements, which include all packaging materials around the individual unit.
• Loose packaging inflates your dimensions — Amazon's automated sensors measure edge-to-edge, capturing loose poly bag material, protruding handles, and any packaging that extends beyond the product. This can push your item into a larger, more expensive size tier.
• Multiple fee types are affected — Item package weight and dimensions feed into FBA fulfillment fees, monthly and long-term storage fees, removal and disposal fees, inbound placement service fees, and prep service fees.
• You can request remeasurement — If you believe Amazon has recorded incorrect dimensions for your FNSKU, you can submit a remeasurement request. Amazon will locate a sellable unit in their fulfillment center and re-evaluate it, typically within 10 days.
• Monthly remeasurement limits apply — Each account has a cap on how many remeasurement requests can be submitted per month, based on the number of active offers with inventory. The count resets on the first of each month.

How Amazon Measures Your Packages

Amazon uses automated measurement sensors positioned throughout its fulfillment centers to capture item dimensions. These sensors evaluate your item package edge-to-edge, meaning they measure the full extent of the packaging as it sits on a flat surface. The longest edge becomes the length, the second longest becomes the width, and the shortest becomes the height. If any dimension varies due to bulging or irregular shape, Amazon measures the thickest or longest point of that dimension. This is important because even small variations — a slightly puffy poly bag or a handle that sticks out — can change your recorded measurements and potentially bump your product into a higher fee tier.