PackOS Pack

Live shipping rates priced to the right box, not guesswork

by PackOS · Launched: May 2026

0.0 on Shopify Built for Shopify

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PackOS selects the correct box for every order and returns accurate live carrier rates at checkout.

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About PackOS Pack

PackOS solves the problem of inaccurate shipping rates at checkout. When box size is estimated incorrectly, merchants either overcharge customers and lose carts, or undercharge and lose margin. PackOS uses bin-packing logic to determine which box an order actually fits in, then queries live rates from USPS, UPS, FedEx, and other carriers for that specific package. Merchants configure their box inventory once, set their carrier preferences, and PackOS handles the rest automatically at checkout. Bin-packing engine selects the recommended box for each order automatically Live carrier rates from USPS, UPS, and FedEx returned at checkout Configurable box inventory, carrier settings, and shipping rules Show more Show less

Last verified: July 21, 2026 · Fresh