Picking a barcode is not a matter of taste: the data you carry,
the space you have and the device that will read it already narrow the choice a
long way. Three questions settle most cases.
1. What is the data?
A retail product number (GTIN) → EAN-13, or EAN-8 on small
packaging; UPC-A/UPC-E in North America. These carry no free text: the digit
count is fixed and there is a check digit.
A tracking number, serial or batch code → Code 128. It
encodes the full ASCII set at high density and is the de facto standard for
shipping and warehouse labels.
A URL or multi-line text → QR. Readable with a phone camera
and strong on error correction.
An outer case (GTIN-14) → ITF-14, which prints directly onto
corrugated board.
2. How much room is there?
Linear (1D) barcodes grow horizontally as the data gets longer; on a
narrow label a long Code 128 either squeezes past readability or overflows. Two
dimensional codes fit the same data into a square: Data Matrix
for very small surfaces (electronic parts, pharmaceutical cartons),
QR where easy scanning matters more.
When space is genuinely tight, moving to 2D is almost always better than
shrinking a 1D code: reducing the module width is what makes a barcode
unreadable.
3. What will read it?
This question gets skipped most often and causes the most expensive mistake.
The laser scanner at a supermarket checkout does not read 2D codes; QR
is only read by camera-based scanners and phones. If the other side is a carrier
or a retail chain, the symbology is not your choice — it is in their
specification.
The short version
Scanned at a checkout → EAN-13
Shipping/warehouse, variable-length data → Code 128
Scanned by phone, contains a link → QR
Very small surface, industrial/pharma → Data Matrix
Outer case packaging → ITF-14
Do not assume the character set and length your chosen symbology accepts —
test it. The same data can be valid in one symbology and invalid in another.
Frequently asked questions
When is Code 128 the better choice over EAN-13?
EAN-13 exists for retail product codes: exactly 13 digits, read at checkouts. Code 128 encodes arbitrary alphanumeric data compactly, which makes it the usual default for logistics and internal labels.
When is a QR code the wrong choice?
When the reader is a classic laser scanner — lasers read only 1D codes. A QR code needs a camera-based reader; choose it for URLs and larger payloads, not for existing 1D scan lines.
What if there is very little space on the label?
With a camera reader available, Data Matrix usually fits where a 1D code will not. Shrinking a 1D barcode below its minimum bar width just makes it unreadable.
