Weight of 1st class mail

The weight of 1st Class Mail in the United States is as follows:

• Letters (up to 3.5 oz): $0.55
• Large Envelopes (up to 13.5 oz): $0.95
• Flat Rate Envelopes (up to 13.5 oz): $7.35
• Padded Envelopes (up to 13.5 oz): $7.35

Note: These prices are subject to change, so it's always best to check with the United States Postal Service (USPS) for the most up-to-date information.

Here are some general guidelines for the weight limits of 1st Class Mail:

• Letters: Up to 3.5 oz (100g)
• Large Envelopes: Up to 13.5 oz (384g)
• Flat Rate Envelopes: Up to 13.5 oz (384g)
• Padded Envelopes: Up to 13.5 oz (384g)

If your mailpiece weighs more than the maximum weight limit, you will need to use a different class of mail, such as Priority Mail or Parcel Post.