On this page, you can download package size limits of USPS Priority and USPS Express delivery methods, as well as size limits for Planet Mail Economy and Planet Mail Express.
Planet Mail Economy & Planet Mail Express
The size limit for Planet Mail Economy and Planet Mail Express is the same for all countries.
Max Weight: 4.3 lbs
Max Lenght: 24 inches.
Max Overall Size* 36 inches
*Max Overall Size is counted as L+W+H.