BarcodeFAQ.com provides
basic bar code information including answers to frequently asked questions,
barcode tutorials and product recommendations for printing and scanning
barcodes.
|

Information on this website is provided
courtesy of IDAutomation.com, Inc.
|
| What
data is encoded in various barcodes? |
Some barcode types, or symbologies, encode only numbers while others encode
letters and numbers. Other barcode types can actually encode files, pictures
and other binary data. Here is a basic breakdown of a few barcode types
and what they encode:
| Barcode
symbology |
Types
of data encoded |
|
Code 39 |
Numbers and upper case letters with a few symbols |
|
Code 128 |
All numbers, letters and punctuation plus ASCII
0 to 127 |
|
Data
Matrix |
All numbers, letters and punctuation, ASCII
0 to 127 plus files and bytes. |
|
Interleaved
2 of 5 |
Numbers only |
|
MSI Code |
Numbers only |
|
PDF417 |
All numbers, letters and punctuation, ASCII
0 to 127 plus files and bytes. |
|
Postnet |
Numbers only |
| IDAutomation
has compiled some recommendations for bar-coding: |
If the intended use of the barcode fonts is for printing, check the
type of data to encode:
- Only numbers, up to about 20 digits, choose
Codabar
or Interleaved
2 of 5. Codabar is the most dense self-checking symbology. ITF
is a numeric-only barcode used for encoding pairs of numbers in a high
density barcode format.
- Only uppercase letters, numbers and these symbols (- . $ / + %),
up to about 15 digits, choose
Code 39.
Code 39 is the most dense self-checking alpha-numeric barcode type.
- Uppercase and lowercase letters, numbers, punctuation, any letter
or symbol appearing on the US 101 key keyboard and lower ASCII functions
such as returns and tabs, up to about 20-30 digits, use
Code 128.
- Several lines of data of any type over 20 digits, use
PDF417 or
Data Matrix.
If the intended use is a barcode component or
label printing application,
check the type of data to encode:
- Uppercase or lowercase letters, numbers, punctuation, any letter
or symbol appearing on the US 101-key keyboard and lower ASCII functions
such as returns and tabs, up to about 20-30 digits, use Code 128
which is in the Linear
ActiveX Control,
Label Printing Programs,
ASP components for
IIS,
.NET Forms Controls,
ASP.NET Server
Controls or the
Java Bar Code Products.
- Several lines of data of any type over 20 digits, use PDF417
or Data Matrix which is in the
ActiveX Control,
.NET Barcode Forms
Controls,
ASP.NET Server Controls,
2D Barcode Fonts,
Label Printing Barcode
Programs, ASP
components for IIS or the
Java Products.
In a study at
Ohio University, several different bar code symbologies were tested
to determine their accuracy and are listed below. Keep in mind that a well-trained
data entry operator will usually make a data entry error once every 300
keystrokes. Therefore, even implementing the least accurate symbology is
a huge step forward to increase production and reduce data entry errors.
The most inaccurate symbology (UPC) is used in the retail industry.
| Barcode Type |
Worst Case Accuracy |
Best Case Accuracy |
| Data Matrix |
1 error in 10.5 million |
1 error in 612.9 million |
| PDF417 |
1 error in 10.5 million |
1 error in 612.4 million |
| Code 128 |
1 error in 2.8 million |
1 error in 37 million |
| Code 39 |
1 error in 1.7 million |
1 error in 4.5 million |
| UPC |
1 error in 394 thousand |
1 error in 800 thousand |
|