What weight is first class mail

In the United States, the weight limits for First Class Mail are as follows:

• Letters: Up to 3.5 ounces (99 grams)
• Large Envelopes (Flats): Up to 13 ounces (368 grams)
• Cards: Up to 3.5 ounces (99 grams)
• Postcards: Up to 1 ounce (28 grams)

If your mailpiece weighs more than these limits, you'll need to use a different class of mail, such as Priority Mail or Parcel Post.

Here are some additional details:

• Letters: If your letter weighs more than 3.5 ounces, you can use a larger envelope or a package, but you'll need to use Priority Mail or Parcel Post.
• Large Envelopes (Flats): If your flat weighs more than 13 ounces, you'll need to use Priority Mail or Parcel Post.
• Cards: If your card weighs more than 3.5 ounces, you can use a larger envelope or a package, but you'll need to use Priority Mail or Parcel Post.

Keep in mind that these weight limits apply to the total weight of the mailpiece, including any enclosures, such as photos, brochures, or other materials.