Post office mail sizes

Here are the standard mail sizes and dimensions for the United States Postal Service (USPS):

Letters

• Maximum size: 11.5 inches (29.2 cm) long, 6.125 inches (15.6 cm) high, and 0.25 inches (0.64 cm) thick
• Minimum size: 3.5 inches (8.9 cm) long, 5 inches (12.7 cm) high, and 0.007 inches (0.18 mm) thick
• Weight limit: 3.5 ounces (99 grams)

Large Envelopes (Flats)

• Maximum size: 12 inches (30.5 cm) long, 15 inches (38.1 cm) high, and 0.75 inches (1.9 cm) thick
• Minimum size: 6.125 inches (15.6 cm) long, 11.5 inches (29.2 cm) high, and 0.007 inches (0.18 mm) thick
• Weight limit: 13 ounces (369 grams)

Packages

• Maximum size: 130 inches (330.2 cm) long, 130 inches (330.2 cm) high, and 108 inches (274.3 cm) wide
• Minimum size: 1 inch (2.5 cm) long, 1 inch (2.5 cm) high, and 1 inch (2.5 cm) wide
• Weight limit: varies depending on the service used (e.g., Priority Mail, Parcel Post)

Special Sizes

• Postcards: 3.5 inches (8.9 cm) long, 5 inches (12.7 cm) high, and 0.007 inches (0.18 mm) thick
• Catalogs: 12 inches (30.5 cm) long, 15 inches (38.1 cm) high, and 0.75 inches (1.9 cm) thick
• Booklets: 6.125 inches (15.6 cm) long, 9 inches (22.9 cm) high, and 0.25 inches (0.64 cm) thick

Please note that these are general guidelines and specific sizes may vary depending on the type of mail piece, the service used, and the destination. It's always a good idea to check with the USPS for specific size and weight limits for your mail piece.