1D Barcode Specifications

Updated on Aug 20, 2026

One-dimensional (1D) barcodes are made up of lines and spaces of various widths that create specific patterns.

The following table describes the specific characteristics of the barcodes per type.

Barcode Type	Image	Description	Character Set	Length	Check Digit
Codabar		Codabar is a discrete, self-checking symbology that may encode 16 different characters, plus an additional 4 start/stop characters.	0123456789-$:/.+	variable (no fixed length)	Calculated according to Modulo 16
Code 11		Code11 is a barcode symbology which is discrete and is able to encode the numbers 0 through to 9, the dash symbol (-), and start/stop characters	0123456789-	variable (no fixed length)	Calculated according to Modulo 11
Code 25 Standard		Standard 2 of 5 is a low-density numeric symbology. The spaces in the barcode exist only to separate the bars themselves. Additionally, a bar may either be wide or narrow, a wide bar generally being 3 times as wide as a narrow bar. The exact size of the spaces is not critical, but is generally the same width as a narrow bar.	0123456789	variable (no fixed length)	Calculated according to Modulo 10
Code 25 Interleaved		Interleaved 2 of 5 is a higher-density numeric symbology based upon the Standard 2 of 5 symbology. Interleaved 2 of 5 encodes any even number of numeric characters in the widths of the bars and spaces of the bar code. Unlike Standard 2 of 5, which only encodes information in the width of the bars, Interleaved 2 of 5 encodes data in the width of both the bars and spaces. This allows Interleaved 2 of 5 to achieve a somewhat higher density. The symbology is called "interleaved" because the first numeric data is encoded in the first 5 bars while the second numeric data is encoded in the first 5 spaces that separate the first 5 bars. Thus, the first 5 bars and spaces actually encode two characters. This is also why the bar code can only encode an even number of data elements.	0123456789	variable (no fixed length), but even	Calculated according to Modulo 10
Code 39		Code39 is a barcode symbology which encodes alphanumeric characters into a series of bars. It is of variable length and accepts uppercase letters, as well as numbers.It includes an optional Mod 43 checksum.	0123456789[Space] ABCDEFGHIJKLMNO PQRSTUVWXYZ-.$/+%	variable (no fixed length)	Calculated according to Modulo 43
Code 39 Extended		Code39Extended is an extended version of code 39, which includes a bigger character set. If there is a requirement to use the Code39 barcode with characters other than numbers and uppercase alphabets, then this is the recommended barcode.	0123456789[Space] ABCDEFGHIJKLMNO PQRSTUVWXYZ!#$%&'() *+,-./:;<=>?@[]^_` abcdefghijklmnopqrstuvwxyz{|}	variable (no fixed length)	Calculated according to Modulo 43
Code 93		Code93 was designed to complement and improve upon Code 39. Code 93 is similar in that it, like Code 39, can represent the full ASCII character set by using combinations of 2 characters. It differs in that Code 93 is a continuous symbology and produces denser code. It also encodes 47 characters compared to Code 39's 43 characters.	0123456789[Space]ABCDEFGHIJKL MNOPQRSTUVWXYZ-.$/+%	variable (no fixed length)	Calculated according to Modulo 47
Code 93 Extended		Code93Extended is an extended version of code 93, which includes a bigger character set. Code93Extended can encode full 128 character ASCII using the four additional characters: ($) (%) (/) (+)	0123456789[Space]ABCDEFGHIJKL MNOPQRSTUVWXYZ -.$/+%!#&'()*,:;<=>?@[]^_` abcdefghijklmnopqrstuvwxyz{|}~	variable (no fixed length)	Calculated according to Modulo 47
Code 128		Code128 is a barcode symbology which encodes alphanumeric characters into a series of bars. It is of variable length, and accepts numbers, upper and lower case characters. It also includes an obligatory MOD 103 checksum. The Code128 is divided into three subsets A, B, and C. There are three separate start codes to indicate which subset will be used.	!"#$%&''()*+,-./ 0123456789:;<=>?@ ABCDEFGHIJKLMNO PQRSTUVWXYZ[]^_` abcdefghijklmnopqrstuvwxyz{|}Space, Control characters: ASCII 1-31,127	variable (no fixed length)	Calculated according to Modulo 103
Code 128 A		Code128A supports the standard ASCII symbols, numbers, upper case letters, and control characters such as tab and new-line.
Code 128 B		Code128B supports standard ASCII symbols, numbers, upper and lower case letters.
Code 128 C		Code128C supports numbers only.
MSI		MSI(also known as Modified Plessey) is a barcode symbology, a continuous, non-self-checking symbology. It is used primarily for inventory control, marking storage containers and shelves in warehouse environments. The length of this barcode type is variable.	01234567890	variable (no fixed length)	The MSI barcode uses one of four possible schemes for calculating a check digit: MSImod10(most common), MSImod1010, MSImod11, MSImod1110
EAN 8		EAN8 is a barcode symbology which encodes numbers into a series of bars. It is of fixed length, of 7 digits, and accepts numbers only. It includes a checksum.	01234567890	8	Calculated according to Modulo 10
EAN 13		EAN13 is a barcode symbology which encodes numbers into a series of bars. It is of fixed length, of 13 digit (12 data and 1 check), and accepts numbers. First digit is always placed outside the symbol; additionally a right quiet zone indicator (>) is used to indicate Quiet Zones that are necessary for barcode scanners to work properly. It includes a checksum.	01234567890	13	Calculated according to Modulo 10
Postnet		Postnet(Postal Numeric Encoding Technique) is a barcode symbology which encodes numbers into a series of bars. It is of variable length and accepts numbers only. It includes a checksum. The POSTNET barcode was replaced by the Intelligent Mail barcode in the fall of 2009.	01234567890	variable (no fixed length)	The check digit is calculated as follows: First add all digits. The difference of this sum to the next multiple of 10 is the check digit.
Planet		The Postal Alpha Numeric Encoding Technique (PLANET) barcode was used by the United States Postal Service to identify and track pieces of mail during delivery - the Post Office's "CONFIRM" services. It was fully superseded by Intelligent Mail Barcode by January 28, 2013.	0123456789	A PLANET barcode appears either 12 or 14 digits long.	Calculated according to Modulo 10
Intelligent Mail		The Intelligent Mail Barcode (IM barcode) is a 65-bar barcode for use on mail in the United States. The IM barcode is intended to provide greater information and functionality than its predecessors POSTNET and PLANET.	numeric	20, 25, 29 or 31	CRC check
GS1-128		GS1-128 is a special form of Code 128. It is used for goods and palettes in commerce and industry. The name GS1-128 replaces the old name EAN/UCC 128.	alphanumeric	variable (no fixed length)	Calculated according to Modulo 103
UPC A		UPC A is a barcode symbology, which consists of 12 digits, one of which is a checksum. This barcode identifies the manufacturer and specific product, so point-of-sale cash register systems can automatically look up the price.	01234567890	12 bzw. 8	Calculated according to Modulo 10
UPC E		UPC E is a variation of the UPCA symbol that is used for number system 0. By suppressing zeroes, UPCE codes can be printed in a very small space and are used for labeling small items.	01234567890	8 bzw. 6	Calculated according to Modulo 10
UPC Supplement 2		A two digit UPC supplementary code. This barcode should only be used with magazines, newspapers and other such periodicals.	0123456789	2	none
UPC Supplement 5		A five digit UPC supplementary code. This barcode is used on books to indicate a suggested retail price.	0123456789	5	none

Example with Code39 symbology

Apply the Code39 symbology to a RadBarcode.

XAML

<telerik:RadBarcode WidthRequest="200" HeightRequest="100"
        HorizontalOptions="Center" VerticalOptions="Center"
        Value="58000106">
    <telerik:RadBarcode.Symbology>
        <telerike:Code39 HorizontalTextAlignment="Center"
                          SizingMode="Stretch"
                          ShowText="True"  
                          CodeTextSpacing="10"/>
    </telerik:RadBarcode.Symbology>
</telerik:RadBarcode>

Add the following namespace.

XAML

xmlns:telerik="http://schemas.telerik.com/2022/xaml/maui"

The following image shows the result from the suggested implementation.

See Also

• 1D Barcodes Overview