Hold shift to drag to/from boxes around
Page setup:
wide × high (valid units: in, cm, mm, pt)
Or use preset:

Printing instructions:
  1. Select envelope size and options
  2. Fill in addresses above
  3. Set envelope in your printer
  4. Print this web page

Once you get it working, bookmark this link to come back to this page with all the settings in place just as they are now.

Good page for finding US postage price

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