Which barcodes it reads
Barcodes come in many families, and which one you have depends on where it is printed. This scanner reads the ones you are most likely to meet:
- EAN-13, EAN-8, UPC-A and UPC-E: the barcodes on products in shops. A UPC-A is reported as 13 digits with a 0 in front, which is the same number as an EAN-13 and how phones and tills report it too. A UPC-E is the short, 8 digit form of a UPC-A for small packs. The result shows the 8 digits printed on the pack, the 12 digit UPC-A it stands for, and the 13 digit form.
- Code 128: shipping labels, parcel tracking numbers, warehouse and asset tags.
- Code 39 and Code 93: older industrial, defence and ID badge labels.
- ITF and ITF-14: the 14 digit numbers on outer cartons.
- Codabar: libraries, blood banks and some older parcel labels.
- GS1 DataBar: small items and fresh food. A DataBar is shown as its GS1 data, for example a number that starts with 01.
- QR, Data Matrix, PDF417 and Aztec: 2D codes, which are read when they are in the same picture. For QR codes with links, Wi-Fi details and contacts, the QR code scanner is built for them.
What a barcode number tells you, and what it does not
A product barcode holds a number and nothing else. The number is the key to a record in a catalogue, and the record, not the barcode, holds the name, the maker and the price. This scanner reads the number and does not look it up. A lookup would mean sending what you scan to a server, which this site does not do. To find out what a number is, search for it yourself.
The first digits of an EAN-13 show which GS1 office issued the company prefix. They do not say where the product was made. Numbers starting with 978 or 979 are ISBNs for books, and 977 is for magazines. When you scan one of these, the result says so.
The last digit of an EAN, UPC or ITF-14 number is a check digit worked out from the others. The decoder only accepts an EAN or UPC that passes it, which is why a smudged barcode usually fails to read instead of reading wrong. Code 128 has a built in check that works the same way.
Getting a good read
Barcodes have no repair data like a QR code does. Nothing can be filled in when part of one is missing, so a read either works or it does not. What helps:
- Light and focus. Even light, with no glare across the bars. Hold the phone far enough away for the camera to focus, and let it settle for a moment.
- Level. Hold the barcode level in the frame, and fill most of the width with it. The scanner also tries some tilt, but a level barcode is quickest.
- The whole barcode. From the first bar to the last, with blank space at both ends. A barcode that is cut off will not read.
- Flat labels. A label on a curved bottle or a crumpled bag bends the bars. Press it flat if you can.
- Pictures. A sharp screenshot or scan beats a blurry photo. If the bars are only 1 pixel wide in the picture, the picture is too small, so enlarge the barcode on screen first and take a new screenshot.
If a picture fails, the scanner has already tried it turned each way, stretched and enlarged. Crop closer, retake the photo or scan from the camera.