SAMPLE CALCULATION FROM USPS SITE

This is a example , based on 4 pounds , of how much the postage cost varies depending on the method used :

International Calculator

First, how quickly do you want it delivered to Australia?

International mail service options based on selected mailpiece size, weight and destination country.

Service	Speed*	Price	Dimensions
Global Express Guaranteed Document Service (See Service Guide Before Mailing)	2 - 3 Days	$66.00	Max. length 46", width 35", height 46" and max. length plus girth 108"
Global Express Guaranteed Non-Document Service (See Service Guide Before Mailing)	2 - 3 Days		Max. length 46", width 35", height 46" and max. length plus girth 108" Calculate Price based on Dimensional Weight.
Global Express Mail (EMS)	3 - 5 Days	$32.00	Max. length 36", max. length plus girth 79"
Global Priority Mail - Flat-rate Envelope (large)	4 - 6 Days	$9.00	9-1/2" x 12-1/2"
Global Priority Mail - Flat-rate Envelope (small)	4 - 6 Days	$5.00	6" x 10"
Global Priority Mail - Variable Weight (single)	4 - 6 Days	$27.00	Max. length 24", Max. length, height, depth combined 36"
Airmail Letter Post	4 - 7 Days	$25.90	Max. length 24", Max. length, height, depth combined 36"
Airmail Parcel Post	4 - 10 Days	$26.75	Max. length 42", max. length plus girth 79"
Economy (Surface) Letter Post	4 - 6 Weeks	$11.45	Max. length 24", Max. length, height, depth combined 36"
Economy (Surface) Parcel Post	4 - 6 Weeks	$21.50	Max. length 42", max. length plus girth 79"

*Designed to be delivered in the number of business days specified for each service depending on origin and destination.