Size of postcard for mailing

The standard size for a postcard that can be mailed in the United States is 3.5 inches by 5 inches (8.9 cm x 12.7 cm). This size is specified by the United States Postal Service (USPS) and is commonly referred to as a "standard postcard."

However, it's worth noting that the USPS also allows for larger postcards, known as "large postcards," which can be up to 4.25 inches by 6 inches (10.8 cm x 15.2 cm) in size. These larger postcards are considered to be a special class of mail and may require additional postage.

Here are some general guidelines for the size of postcards that can be mailed:

It's always a good idea to check with your local post office or the USPS website for the most up-to-date information on postcard sizes and mailing requirements.