You really need to experiment with Google searches if
you actually had difficulty finding the postal rate information
on the Internet. Go to Google and enter:
Either way, the first website listed is the US Postal Service.
The second tab at that webpage is "Calculate Postage,"
and that page has an extremely obvious tab labeled "rates
It is pretty easy to find information on just about anything
with Google, but it does take a bit of experimentation and
practice to get the nack. Once you've mastered it, it will
be impossible to imagine living without it.