Question: usps does weight have to be exact?
Answer: Weigh Your Item and Round Up USPS rounds up to either the next pound (lb) or ounce (oz). For example, if your package weighs 3 lbs 5 oz, it would be charged at the 4 lb-rate. If you have an item for shipping by First-Class Package® service that weighs 7.3 oz, it must be charged at the 8 oz-rate.