What is Standard 2 of 5?
Standard 2 of 5 - also called Industrial 2 of 5 - is one of the oldest numeric-only barcodes. Only its bars carry information (the spaces are fixed width), which makes it less dense than Interleaved 2 of 5 but extremely tolerant of low-resolution printing. It still appears in warehouse and industrial systems, airline legacy formats and photo finishing where long-lived scanners were configured for it.
Common Uses for Standard 2 of 5
- Warehouse and industrial numeric part/bin labels
- Legacy airline and baggage tag formats
- Photo finishing envelopes and film labelling
- Systems whose scanners specify Standard/Industrial 2 of 5
Why bars-only encoding matters
In Standard 2 of 5 each digit is five elements: two wide bars among narrow ones, separated by fixed-width spaces that carry no data. That structure is why the code tolerates dot-matrix and rough thermal printing - the readable signal lives entirely in the bars - and also why it needs roughly twice the width of Interleaved 2 of 5 for the same number. For new designs with decent printers, Interleaved 2 of 5 or Code 128 are the better defaults.
The optional modulo-10 check digit
Because Standard 2 of 5 is not self-checking, a misprint can turn one digit into another without detection. A modulo-10 check digit - computed with the same 3-1-3-1 weighting used by EAN and ITF-14 - lets the scanner reject a bad read. If your warehouse or airline system was configured with a check digit, append it to every value before generating; if it was configured without one, keep values consistent or scanners will reject the labels.
Standard 2 of 5 variants (IATA, Matrix, COOP)
Several close relatives of Standard 2 of 5 exist: IATA 2 of 5 was used on airline tickets and baggage documents, Matrix 2 of 5 thins the inner spaces for better density, and COOP 2 of 5 saw warehouse use. They are not interchangeable - a scanner configured for one variant will misread another. Identify the exact variant your system expects; if documentation simply says 2 of 5, Standard 2 of 5 as generated here is the usual meaning.
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