USPS Barcode No Postmark

I'm trying to determine when a large envelope was sent but there's no postmark, just a post-mailing barcode applied on a sticker affixed to the envelope. Was wondering anyone had insights on how to read the USPS barcode? I thought it might be an IMb code, but it's my understanding that's supposed to be 65 digits and mine is only 57. Any ideas? Any help would be greatly appreciated.

Hi windcriesmary and welcome to this forum. I get those also, but in my case it is because the stamps have no tagging and the canceller machine does not know there is a stamp on it.

Peter

It is not unusual for the stamps on a large envelope to miss being cancelled. As to the bar code, I believe that it will provide information to you address, but not from where the mailing originated.

It depends on the type of barcode and label.

I have a engineering background in scanning technology (I worked on several projects over the years which developed the hardware and software for many of the commercial handheld scanners in the marketplace). As such, I happen to have some scanners kicking around the house.


When I scan this label the two bar codes return different results. The simple 1D barcode on the bottom return just the tracking number, in this case # 420287399400111899563096604715. The 2D bar code on the top returns a very large amount of information including addresses, description of mail service, weight, date info, etc. (I have a hard time scanning this one because it sends all kinds of extra commands like carriage returns. The scanner software on my computer handles scanner input as keyboard input.)



This barcode scans as 000685.


In general the older 1D barcodes only contain a single number. The 2D barcode technologies can contain a very large amount of data.
Don
APS #094826

Edit; if you want to know about your particular barcode, scan it in 300 dpi resolution and post the image. I should be able to scan it off the screen and tell you what it reads.

Don, I think he is not talking about that barcode.
There is a barcode that is sometimes found on covers on the bottom, consisting of some 60 small vertical dashes. Also followed by an 11 digit Zip code. I get a magazine from England wrapped in plastic and it has the same type barcode on it, printed on a piece of tape.

Peter