I sent 3 books to a member who had requested them. One book was hard cover, the other two paperback. I put them in a box. PBS charged $3.88 postage. When I put books in a box I take them to the post office just to make sure I have enough postage. The package weighed 2 lbs, PBS had estimated a little under 4 lbs so charged the 4 lb rate. Needless to say I had more than enough postage. I can appreciate it'shard to know exactly what a potential set of books will weigh but......

The weights in the PBS database come from many sources, and sometimes they are incorrect. Also, it is possible that the same ISBN is used for more than one edition of a book ... so the same ISBN might be applied to a mass market paperback and a trade sized edition of a book. Obviously, the weight can only be correct for one of those copies, but not both.

If you are inclined to fix the database, you can Edit the Book Data and put in the correct weight for a book.

I think that most people who print postage from the site also use a scale to weigh the packages at home.

There are millions of books in the database, all of them with the data coming from outside sources or from members manually keying in the information. The only data editing done is by members volunteering to do it. You are welcome to edit any books you find to be in error, you can find the like to submit a Book Data Edit on the books details page and can also work on other books in the data base through Members Tools in the lower left. You can also joing the Data Team to become more involved in the process!

Anytime you are using PBS postage it is recommended to confirm the weight. Especially in a bulk mailing when you are using an alternate packaging.

A good investment is a postal scale!  I got one for roughly $13 but in the long run, it's saved me money along the way because I mail so much & you can't assume the weights on PBS are always correct.

PBS postage is often wrong, which is one reason I take my books to the PO to mail.  Sometimes the postage on PBS is higher than the PO charges.  Sometimes 1st class is cheaper.  Sometimes the weight that PBS has is wrong (had a PB once that PBS said weighed 9 lbs.  Think it really weighed 9 ozs, but someone put a period in the wrong place).  Pat

I agree that having a postage scale or at least a kitchen scale that measures ounces is crucial when I print out postage.

Here is the help doc on this:

The *recommended postage* on my wrapper is/was wrong!

The 'recommended postage' on the PBS wrapper is usually correct, but not always. Our database is compiled elsewhere, and it includes some inaccuracies, including the weight of some books. The weight of a book as recorded in the database determines the "required postage" that appears on the PBS Wrapper.

You can see, and adjust, the weight estimate on the Wrapper Settings page when you go to print a wrapper.  Adjusting it to the correct weight will ensure that correct postage prints out.  If you do not have a postal scale, you can take the wrapped book to the PO to be weighed.

This is particularly important if you are using PBS Printed Postage--check and adjust the weight before you print!  Printed Postage can't be refunded after it is printed.

If you want to change the weight of the book in the database permanently, so that no one else has trouble with this for this book in future, you can submit a correction to our Data Correction volunteers.

• To submit the correct weight of a book to the PBS Database:

1. Click "More Options" to the right of the book cover image on the Book Details page and choose Edit Book Data from the dropdown menu (you can also access Edit Book Data from the Member Tools page, which is linked from the bottom of any page on the site).
2. Enter the ISBN for the book and click Next->
3. Enter/adjust the weight of the book (this will be on your postal receipt) on the next page, leaving any correct information in place
4. Click Submit.

• This information will be submitted to our editing volunteers, and the database should be corrected in a few days.

Please know that any effort you make to improve the accuracy of the database is greatly appreciated.

It is quite possible that PBBS estimated the weight of the box with three books in it by adding up the estimated weights of each individual book, which would obviously include two additional envelopes/boxes that you weren't using.