Amazon measures your product's dimensions and weight at the fulfillment center.
By Anthony Nguyen 🟢 · July 2, 2026 · Curated by George's Blog
Amazon measures your product's dimensions and weight at the fulfillment center. Those measurements determine your FBA fee tier. And they get it wrong more often than you'd think.
A product that's 14.9 inches on the longest side is "standard size." At 15.1 inches, it jumps to "large standard" or even "oversize." The fulfillment fee increase? $3-5 per unit. For doing nothing wrong.
Common errors:
- Packaging adds 0.5-1 inch that bumps the product into the next tier
- Weight rounded up incorrectly
- Dimensions measured on a damaged or poorly packed unit
- Poly bag or bubble mailer not accounted for properly
How to audit: download your Fee Preview report. Compare Amazon's recorded dimensions against your actual product specs. Any SKU where dimensions are even slightly over a tier boundary is worth investigating. I guarantee you'll find at least one.
If you find an error, open a case with Seller Support and request a "cubiscan" remeasurement. Include your own measurements with photos showing a ruler or tape measure. Be specific. Be persistent.
The overcharge applies to every unit sold. A $2 per-unit overcharge on a product selling 500 units per month is $12,000 per year from a single SKU. That's not a rounding error. That's a car payment.
Check your top 20 SKUs by volume first. That's where measurement errors cost the most.
AdsCrafted runs these audits in one command, P&L, reimbursements, catalog health, AMC queries, all conversational → adscrafted.com