Supported Symbologies

While still growing, clickBarcode.com supports many common barcode formats, also known as symbologies. Each one has its own unique properties and uses, which are explained below. If you would like to see a new symbology added to the clickBarcode site, or see areas where the site can improve, please contact us with your ideas, suggestions, or even questions.

Alphanumeric Symbologies

Code 128

Code 128 is one of the most versatile barcode formats, as it can encode all 128 of the standard ASCII characters. This includes all upper and lower case letters, numbers, punctuation, and special control characters. A 'check character' is included at the end of every barcode as an error-checking measure to prevent misreads. In most situations, each character is encoded as a series of 3 bars and 3 spaces of varying widths. However, to minimize the size of the barcode, Code 128 can encode sets of two numbers into the same series of 3 bars and spaces. This effectively shrinks portions of the barcode to half size, requiring fewer bars and spaces, allowing the barcode to be scanned more easily. The Code 128 generator on clickBarcode will automatically switch between single or double density encoding when needed to produce a barcode with the most efficient usage of bars and spaces.

Code 39

Also known as Code 3 of 9, Code 39 is one of the most basic alphanumeric barcodes available, supporting uppercase letters, numbers, and limited punctuation. The drawback of Code 39 is its low data density, requiring more bars and spaces than other available symbologies. However, because of its widespread use, most barcode readers will read Code 39 with no trouble.

Numeric Symbologies

UPC A

The most common barcode format in the United States, the UPC-A barcode can be found on almost any retail product, and is easily scanned by almost any barcode scanner. The format encodes 12 numbers. The first 11 can be set to any value, while the 12th digit is an automatically calculated 'check digit' used for error checking purposes, used to prevent misreads.

Interleaved 2 of 5

Interleaved 2 of 5 is based on the "2 of 5" standard, which encodes numbers as a series of Narrow or Wide bars or spaces. Each number contains 5 narrow or wide elements, two of them are always wide. The Interleaved format uses both the bars and the spaces to encode 2 numbers for every 5 bars and 5 spaces. The first digit is represented by the first 5 bars, the next by the first 5 spaces, and so on. In some cases, a check digit is used, but not necessary. Since this format encodes numbers in pairs, only an even number of digits can be encoded.

Standard 2 of 5

Also known as "Industrial 2 of 5," this format was the original symbology based off of the "2 of 5" standard. Numbers are encoded as a series of 5 narrow or wide bars. However, since its data is encoded in the bars only, the spaces do not contain any critical information. As a result, this is a rather low density barcode, requiring more space to encode information than other formats.

2-Dimensional Symbologies

Currently, clickBarcode does not support any 2D symbologies. If you would like to see 2D barcodes supported here, feel free to contact us!