Our postage label provider maintains a convenient list of the various package type restrictions, copied below:

Predefined Package NameDimensionsWeight
Card
  • Min: 3 1/2“ x 5 1/2"
  • Max: 4 1/4” x 6”
Must be a flat surface
Letter
  • Min: 3 1/2” x 5 1/2”
  • Max: 6 1/8” x 11 1/2”
Maximum weight is 3.5 oz.
Flat
  • Min: 6 1/8” x 11 1/2”
  • Max: 12 x 15”
Maximum weight of 13 oz.
ParcelMaximum size is 108" in combined length and girth (distance around the thickest part).Contents for Priority Mail Express, Priority Mail, or Media Mail® must weigh less than 70 lbs. First-ClassTM packages must weigh less than 13 oz.
LargeParcelMaximum size is 130" in combined length and width (distance around the thickest part).Contents must weigh less than 70 lbs.
IrregularParcel
  • Rolls and tubes up to 26 inches long
  • This predefined parcel includes unwrapped, paper-wrapped, or sleeve-wrapped articles that are not letter-size or flat-size (e.g., catalogs, directories).
  • Articles enclosed in envelopes that are not letter-size, flat-size, or machinable parcels.
Contents must weigh less than 70 lbs.
FlatRateEnvelope12-1/2" x 9-1/2"
  • Contents must weigh less than 70 lbs.
  • International Weight limit: 4 lbs.
FlatRateLegalEnvelope15" x 9 1/2"
  • Contents must weigh less than 70 lbs.
  • International Weight limit: 4 lbs.
FlatRatePaddedEnvelope12 1/2" x 9-1/2"
  • Contents must weigh less than 70 lbs.
  • International Weight limit: 4 lbs.
FlatRateGiftCardEnvelope10" x 7"
  • Contents must weigh less than 70 lbs.
  • International Weight limit: 4 lbs.
FlatRateWindowEnvelope10" x 5"
  • Contents must weigh less than 70 lbs.
  • International Weight limit: 4 lbs.
FlatRateCardboardEnvelope12 1/2" x 9-1/2"
  • Contents must weigh less than 70 lbs.
  • International Weight limit: 4 lbs.
SmallFlatRateEnvelope12 1/2" x 9 1/2"
  • Contents must weigh less than 70 lbs.
  • International Weight limit: 4 lbs.
SmallFlatRateBox8 5/8" x 5 3/8" x 1 5/8"Contents must weigh less than 70 lbs.
MediumFlatRateBox11 x 8 1/2 x 5 1/2Contents must weigh less than 70 lbs.
LargeFlatRateBox12 x 12 x 5 1/2Contents must weigh less than 70 lbs.
RegionalRateBoxA
  • Option 1: 10 1/8 x 7 1/8 x 5
  • Option 2: 16 1/6 x 11 1/6 x 2 1/2
Contents must weigh less than 15 lbs.
RegionalRateBoxB
  • Option 1: 12 1/4 x 10 1/2 x 5 1/2
  • Option 2: 16 1/4 x 14 1/2 x 3
Contents must weigh less than 20 lbs.
RegionalRateBoxC15 x 12 x 12Contents must weigh less than 25 lbs.
LargeFlatRateBoardGameBox
  • 23-11/16" x 11-3/4" x 3" – Inside
  • 24-1/16" x 11-7/8" x 3-1/8" – Outside
Contents must weigh less than 70 lbs.

How does Cratejoy calculate shipping?