- This symbology is used by U.S. blood banks, photo labs, libraries, and on FedEx airbills.
- Encodes numbers and the characters –$:/.+
- First and last symbols (the guard patterns) are one of A, B, C, or D. They are returned as part of the data string.
- Supports variable length data content.
- Some standards that use Codabar will define a check digit, but there is no agreed-upon standard checksum algorithm.
- The width ratio between narrow and wide can be chosen between 1:2.25 and 1:3.