A small set of shipping calculators. No account, no upsell.
ShipCompare is built around one question: which carrier, USPS, UPS, or FedEx, is likely cheapest for this specific package.
The Shipping Rate Estimator takes a weight and two ZIP codes and returns a modeled price for all three carriers side by side. The Dimensional Weight calculator takes box dimensions and works out the billable weight a carrier will actually charge, which often runs higher than the number on a bathroom scale.
Both tools run on a rate-tier model built from published carrier pricing structures, not a live connection to any carrier's billing system. The 2026 parcel cost comparison page lays out the tiers and sources in full, including the USPS dimensional weight divisor change taking effect July 12, 2026. The editorial standards page covers how that data gets sourced and kept current.
Comparing three carriers by hand means opening three separate rate pages and doing the zone math yourself. This site does that in one place, in your browser, with no account or email address required.
Guides and calculator copy are written by Marcus Vance. Chris Terry is the publisher of record. The authors page has background on who writes what.