Which barcode symbology fits your data?
Code 128, EAN, GS1-128 and DataMatrix each solve a different task. This guide shows which symbology fits your data content, your part size and your industry standard, and how to avoid mistakes with module width and contrast.
View labels1D or 2D - what is the difference?
Barcodes split into linear 1D codes and area 2D codes. A 1D code such as Code 128 or EAN encodes characters in a sequence of bars and spaces of varying width. A 2D code such as DataMatrix spreads information across a matrix of modules and stores far more characters on the smallest footprint.
The choice depends on three questions: how many characters must be encoded, how much space the part offers and which industry standard applies. Retail requires EAN, electronics manufacturing is dominated by DataMatrix, and logistics mostly uses Code 128 and GS1‑128.
Which symbology for which purpose?
The data content is decisive. EAN-13 encodes exactly 13 digits for the point of sale. Code 128 represents the full ASCII set at variable length. GS1‑128 extends Code 128 with standardised application identifiers (AI), for example batch, expiry date or SSCC. DataMatrix stores up to around 2335 alphanumeric characters on a minimal footprint.
- Digits only and retail sale: EAN-13 or EAN-8.
- Variable characters without industry constraint: Code 128, compact and robust.
- Structured logistics data (batch, expiry, SSCC): GS1‑128 with application identifiers.
- Very little space or direct part marking (DPM): DataMatrix with error correction.
- Marketing and consumer links: QR code as a 2D alternative.
How does part size affect the choice?
The X module width is the smallest element of a code and drives the space needed. A retail EAN-13 has a nominal X width of 0.330 mm, reduced down to about 80 percent. A linear code also needs quiet zones of at least ten times the module width on both sides.
On small parts such as circuit boards, connectors or ampoules that space is missing. This is where DataMatrix excels: a code of 12 x 12 modules already holds a multi-digit serial number on a few square millimetres and needs only a narrow one-module quiet zone all around.
How do you secure readability?
Print quality decides the first-read rate. Linear codes are graded to ISO/IEC 15416, 2D codes to ISO/IEC 15415, each with grades A to F or 4.0 to 0.0. The assessment covers contrast, modulation, decodability and fixed pattern damage, among others.
- Contrast: dark bars on a light background, never red bars (scanners often use red light).
- Keep the quiet zones - missing margins are the most common cause of failure.
- Choose thermal transfer print for durable, smudge-proof labels.
- Match module width to printer resolution (203 or 300 dpi).
- Document verification with a barcode verifier on a sample basis.
Frequently asked questions
What is the difference between Code 128 and GS1-128?
GS1‑128 is technically based on Code 128 but uses the FNC1 character and standardised application identifiers (AI). This lets you encode batch, expiry date or SSCC in a clearly structured way.
When should I use DataMatrix instead of a 1D code?
When space is tight, many characters must be encoded, or you mark directly onto a part. DataMatrix offers high data density and built-in error correction.
Why are red barcodes discouraged?
Many scanners read with red light. Red bars then appear bright and are not detected. Dark bars on a light background give the contrast you need.
How small can a barcode be?
It depends on the X module width and scanner resolution. As a guide, EAN can be reduced to about 80 percent of nominal, while DataMatrix works down to a few square millimetres.
The right symbology for your labels?
We supply labels, ribbons and printers for Code 128, GS1, EAN and DataMatrix - matched to data content and part size.
Standards graded
Quality gradable to ISO/IEC 15415 and 15416.
GS1-compliant
Application identifiers implemented correctly.
Matching materials
Labels and ribbons for every symbology.
Expert advice
Specialists help you choose the symbology.