Opait Barcoder API

Opait Barcoder offers on-line applications to create or detect barcodes in multiple formats. These barcodes can be used, free of charge, in any personal or business application.

The on-line barcodes are great for ad-hoc or personal use. For applications that require high-volume barcode usage or demand tighter integration and control, we offer a desktop version and a powerful .NET API. The API can be used to automate the creation and detection of barcodes for many scenarios. Among these are:

Most of the above mentioned functionality is also available from a flexible command line interface. The command line is ideal for automating barcode applications in batch files and without programing.

The on-line applications on this site use the API exclusively to support:

The API Reference documentation has multiple annotated examples in C#. A typical application only needs a few lines of code.

View API Reference » View Sample Barcodes »


Opait Barcoder can encode and decode the following barcode formats:

  • Aztec Code
    Aztec Code is a two-dimensional (2-D) general-purpose matrix symbology that is designed to have higher accuracy than other 2-D symbologies. An Aztec Code symbol can encode up to 3,832 numeric digits; 3,067 alphabetic characters; or 1,914 bytes of data.
  • Bookland
    Bookland encodes the ISBN number in EAN-13 format followed by a 5-digit supplemental code. The barcode data always consists of the digits ‘978’ (the EAN article identifier), followed by a 9-digit number and one check digit. The 5-digit add-on barcode is used to encode the book price.
  • Codabar
    Codabar is a discrete, self-checking symbology that may encode 16 different characters, plus an additional 4 start/stop characters. This symbology is used by U.S. blood banks, photo labs, and on FedEx air bills.
  • Code11
    Code11 is mainly used in telecommunications for marking equipment and components.
  • Code39
    Code39, also known as "3 of 9 code" or "USD-3", it is the standard barcode used by the United States Department of Defense, and by the Health Industry Bar Code Council (HIBCC). Code 39 is a discrete, variable-length symbology. The character set can be extended to cover the full ASCII range [0..127] and an optional checksum character can be appended to the encoded string.
  • Code93
    Code93 was invented to achieve better information density as compared to code 39. Can also concatenate multiple barcodes using a space as the first character. The extended version covers all ASCII characters.
  • Code128
    Code128 is a modern high-density symbology heavily used in all areas.
    • Code 128: ASCII-characters between 0..127
    • Subset A: Upper Case + Non-Printable Characters (ASCII 0-31)
    • Subset B: Upper / Lower Case + All Printable Characters
    • Subset C: Numeric with doubled density
  • DataMatrix
    DataMatrix is a 2D barcode consisting of black and white "cells" or modules arranged in either a square or rectangular pattern. The information to be encoded can be text or numeric data. Usual data size is from a few bytes up to 1556 bytes. Error correction codes are often used to increase reliability. A Data Matrix symbol can store up to 2,335 alphanumeric characters.
  • EAN2
    EAN2 is a 2-digit add-on for EAN 13 and UPC-A. The EAN2 add-on is often used on newspapers and magazines.
  • EAN5
    EAN5 is a 5-digit add-on for EAN 13 and UPC-A. The EAN5 add-on is often used for the price of books together with the ISBN code.
  • EAN8
    EAN8 is a smaller subset of EAN13.
  • EAN13
    EAN13, also known as Global Trade Item Numbers (GTIN), EAN are for identifying articles or products uniquely. EAN-13 encodes 2-digit country code, 5-digits manufacturer code and a 5-digits products code.
  • FIM
    FIM (Facing Identification Mark) is used by the USPS to assist in the processing of letter mail.
  • GS1-128
    GS1-128, also known as UCC-128 and EAN-128, uses Code128 with application identifiers to specify the format and application area of the encoded values.
  • ITF25
    Interleaved 2 of 5 is a numeric only barcode used to encode pairs of numbers into a self-checking, high-density barcode format. In this symbology, every two digits are interleaved with each other to create a single symbol. An optional Mod10 checksum character can be appended to the code.
  • ISBN
    ISBN is the abbreviation of International Standard Book Number. It uses the symbology EAN-13 and can be optionally extended with 5 Add-On Digits.
  • ITF-14
    ITF-14 is the GS1 implementation of an Interleaved 2 of 5 barcode.
  • JANM
    Japanese Numbering Authority barcodes are EAN codes that use the number system "49".
  • MaxiCode
    MaxiCode is an international 2D barcode that is currently used by UPS on shipping labels for world-wide addressing and package sorting.
  • MSI
    MSI, also known as Modified Plessey, is used primarily to mark retail shelves for inventory control.
  • PDF417
    PDF417 is a 2D barcode (stacked symbology) used in a variety of applications, primarily transport, identification cards, and inventory management. PDF stands for Portable Data File and was developed by Symbol Technologies. PDF417 uses built-in error correction to ensure better readability.
  • Pharmacode
    Pharmacodes are primarily used in pharmaceutical areas.
  • PostNet
    PostNet was developed by the United States Postal Service (USPS) to allow faster sorting and routing of mail.
  • QRCode
    Quick Response Code is a matrix square barcode capable of encoding large amounts of plain text and binary data. Multiple levels of error detection and correction are supported.
  • Standard 2 of 5
    Standard 2 of 5, also known as industrial 2 of 5, is a low density numeric only barcode where digits are encoded with 5 bars, 2 of which are always wide. An optional Mod10 checksum character can be appended to the code.
  • Telepen
    Telepen was designed in 1972 in the UK to express all 128 ASCII characters without using shift characters for code switching, and using only two different widths for bars and spaces.
  • UPCA
    UPCA, also known as GTIN-12, is used in the United States for marking of products in retail applications (similar to EAN).
  • UPC-E
    UPC-E is a variation of UPC-A which allows for a more compact barcode by eliminating "extra" zeros. Since the resulting UPC-E barcode is about half the size as an UPC-A barcode, UPC-E is generally used on products with very small packaging where a full UPC-A barcode couldn't reasonably fit.