What Code One is
Code One is a real, distinct 2D matrix symbology with its own Reed-Solomon error-correction implementation -- confirmed directly: bwipp_codeone calls its own bwipp_rsecbinary(), not another symbology's encoder.
Generate it now
Enter your data (up to 4000 characters) to see a live preview -- bwip-js auto-selects the smallest of 14 real Code One sizes that fits.
Valid input
General text up to 4000 characters is accepted ("The input data is too long" beyond that) for the general-purpose A-H versions. The fixed-length "S-type" versions (S-10/S-20/S-30) accept digits only, up to 18 characters ("S-Type symbols can only contain digits", "Maximum length exceeded"); the compact "T-type" versions (T-16/T-32/T-48) accept a wider character set, including letters.
Key options
The only typed option is version: A through H (general-purpose, increasing data capacity), S-10/S-20/S-30 (fixed-length numeric-only), or T-16/T-32/T-48 (compact). bwip-js's own real default is the sentinel "unset", which auto-selects the smallest size that fits the payload -- unlike rMQR/d3aqr/Mailmark's own required controls, Code One genuinely does auto-select. Code One has no separate configurable error-correction level of its own -- its Reed-Solomon parameters are fixed per version by bwip-js's own internal table.
Output and printing
Export SVG for vector-precise label artwork or PNG for a quick proof.
Common uses
Code One suits compact 2D data labels where a fixed-length numeric or alphanumeric identifier, or general text, needs a small-footprint 2D symbol.
Example
See the live preview above, seeded with a bwip-js-verified valid value.
Size guidance
Overall symbol size grows with the selected (or auto-selected) version, from the smallest general-purpose version A up to the largest, H.
Troubleshooting
A rejected render is usually data too long for the selected fixed version, a non-digit character in an S-type version, an unrecognized explicit version ("version must be A to H, T-16, T-32, T-48, S-10, S-20 or S-30"), or data exceeding the overall 4000-character input limit.
Related formats
Related formats: Data Matrix, QR Code, and Aztec Code (other general-purpose 2D matrix symbologies already in this catalog) -- each is an independently implemented symbology, not a variant of Code One.
FAQ
Does Code One have a configurable error-correction level, like QR Code?
No -- Code One's Reed-Solomon error-correction parameters are fixed per version by bwip-js's own internal table. There is no separate eclevel-style option to raise or lower it.
Do I need to choose a version myself?
No -- leaving version unset lets bwip-js auto-select the smallest of the 14 real sizes that fits your data. Choose one explicitly only if you need a specific fixed size or a fixed-length S-type/T-type variant.