What Japan Post 4 State Customer Code is
Japan Post 4 State Customer Code is a four-state (height-modulated bar) postal barcode used on Japanese mail for automated sorting and addressing.
Generate it now
Enter your postal code and serial data (digits, capital letters, and dashes) to see a live preview -- bwip-js computes and appends the checksum for you.
Valid input
The data may contain only digits, capital letters, and the dash symbol; bwip-js rejects any other character and rejects data past its internal length limit. bwip-js computes and appends its own checksum from whatever data you provide -- it does not independently check that the data follows a real postal code plus serial number structure, so a validly-formatted-looking but incorrect code will still render without error.
Key options
Supported options include includetext and includecheckintext (show the computed checksum character in the human-readable text; only visible when includetext is also on).
Output and printing
Export SVG for mail-piece artwork or PNG for a quick proof.
Common uses
Japan Post 4 State Customer Code appears on Japanese mail pieces to speed automated sorting by postal code and address/serial data.
Example
See the live preview above, seeded with a bwip-js-verified valid postal-code-and-serial value.
Size guidance
bwip-js's own real default bar height, when height is left unset, is 0.175 inch (about 4.4mm).
Troubleshooting
A rejected code is usually a character outside the allowed set (digits, capital letters, and dashes only) or data past the internal length limit.
Related formats
Related formats: USPS POSTNET and USPS Intelligent Mail (comparable postal-automation barcodes for a different postal system).
FAQ
Does this generator validate a real Japan Post address structure?
No -- bwip-js accepts any combination of digits, capital letters, and dashes (up to its internal length limit) and computes/appends the checksum from exactly that data. It does not independently check that the data follows a real postal code plus serial number structure, so double-check your source data before printing.