I am mailing one of those square birthday cards, which says extra postage is required.  Anyone know what the total postage would be?  It's just the card, I haven't added anything to it.

Thanks!

Try USPS.com (the PO website) and go to the "calculate postage" area.  Go to "letter" at 1 oz., and it will give you several shapes of envelope.  This one is 58c, according to them.

The square cards (without any musical gadgets, ribbons or other accroutement) are usually .80

The square cards  with the musical additions (very popular these days)  are usually .97 because of the extra ounce.

Because of the shape of the envelope, they have to go as a first class flat.   The square envelopes generally fall outside of the .58 category because they are considered non-machinable.  The .58 rate is for the second ounce of a normal-shaped envelope....

Size and shape matters in first class mail these days!

Thanks for the responses!  I actually ended up going into the PO this morning just to make sure...and it was .58 cents.