Shipping Calculator is working for who or whom or something? It's costing me $

[fultonfalcon]

I list an item putting it's wt. at 3 lbs.  and let eBay estimate the shipping cost for buyers.... the item sells... when I get it packaged ready to ship, it turns out its only 2.2 lbs..... and Yet I end up having to pay .40 out of pocket Plus the 10% eBay charges me on shipping.... oh sure you say, 40 cents isn't going to break you.....but it's "MY" money.  And ya know, if I miss .10 cents of paying my full eBay bill you'd think I was trying to steal Texas.    The postage calculator is NOT always right.  I know, someone is going to say just add on a surcharge or just put the wt. higher than you think it is.... and someone is going to say wrap the package and get the exact wt. before you sell it.... RIGHT!  So I get to unwrap it every time some turkey wants another measurement.  LOL     JUST how about they FIX the ESTIMATOR ????  It's not like every post office has a different set of rates... or is it?

[remote_controls_and_more]

Priority mail ships by the pound you always round up to next pound. Even 2.01 pounds ships at 3 pounds.

What are the origination and destination zip codes?

[nobody*s_perfect]

The eBay shipping calculator for USPS postage is 99.99% accurate. 

As noted in the other post, your package at 2.2 pounds would ship at the 3-pound rate.

If you tell us the two exact prices that were 40 cents apart, you can probably help you figure out what went wrong.

One surprisingly common glitch happens when the "Shipping from" ZIP Code on the label preparation form doesn't match the ZIP Code for your return address. If the ZIP Code is wrong, then of course the calculated postage will be wrong.

[nodr-45]

You should also check your settings to see if buyers are being charged the retail or online discounted rates. Come back and provide the specific shipping costs @fultonfalcon