About ShipMargin
Why ShipMargin exists and how it helps ecommerce operators make better shipping decisions.
Last reviewed: August 31, 2026
Who we serve
ShipMargin is built for Amazon, Shopify, eBay, and Etsy sellers, DTC brands, 3PL teams, warehouse operators, and small ecommerce businesses.
Why it exists
Shipping invoices often hide the operational cause of a cost increase. ShipMargin turns package dimensions, weight, box fit, and order economics into decisions a small team can act on.
How calculations work
Final calculator outputs use deterministic, versioned formulas. Carrier-specific results require a current verified source. If a source has not been verified, the calculation is disabled rather than guessed.
Report an error
Send the page URL, the result you received, the result you expected, and an authoritative source through the contact or corrections page. Rule changes require review before publication.