As of December 24, 2008, assuming it is no more than one quarter inch thick, and weighs no more than 1 ounce, it only costs 42 cents. Between one ounce and two ounces, 59 cents Between 2 ounces and 3 ounces, 76 cents Between 3 and 3.5 ounces, 93 cents. For the source and complete price listings for first class postage, see http://www.usps.com/prices/first-class-mail-prices.htm
An envelope with a height exceeding 6 and one-eighths inches, and any square envelope, is non-machinable. Therefore, the rate for first class US domestic postage is $.64.
3.000000000
4.5 inches - 6 inches = -1.5 inches.
1/3 * 6 inches= 6/3 inches= 2 inches========
It is: 144 inches by 6 inches or 864 square inches
The postage rate for a standard First Class letter was 6 cents.
Postage depends on the size and weight of the letter you are sending. USPS first-class mail stamps start at forty four cents for letters under two ounces.
The current postcard postage as of the new increase in Jan '09 is: First-Class Mail® Postcards ($0.27 each) Maximum size: 6 inches long by 4-1/4 inches high First-Class Mail® Large Postcards ($0.42 each) More than: 6 inches long by 4-1/4 inches high
11 1/2 inches by 6 1/8 inches
As of August 2012, first class US postage for a 6x9 3.5oz domestic letter is $1.05.
From US First-Class Mail® Postcards ($0.28 eachh Maximum size: 6 inches long by 4-1/4 inches high First-Class Mail® Large Postcards ($0.44 each) More than: 6 inches long by 4-1/4 inches high Domestic and International Postage Price Calculator is here: http://postcalc.usps.gov/Default.aspx
6 soles
For a postcard that is 6 inches long by 4 and 1/4 inches high, first class postage in the US is 27 cents as of June 2008.
An envelope with a height exceeding 6 and one-eighths inches, and any square envelope, is non-machinable. Therefore, the rate for first class US domestic postage is $.64.
6 inches long by 4 and a quarter inches high, .016 inches thick, according to USPS website.
To mail a first class international postcard to Canada, you will need to attach $1.10 in postage. The maximum size for a postcard is 6" in length x 4.25" in height.
Currently (12/19/2009) 44 cents in the US, if the envelope size does not exceed 11-1/2 inches long, by 6-1/8 inches in height.