Royal Mail 2D Mailmark — Barcode Format Guide & Generator
Royal Mail 2D Mailmark is a two-dimensional matrix symbology in the Matrix family. UK Royal Mail Data Matrix-based mark (CMDM). Beyond consumer QR codes, matrix symbols mark surgical instruments, electronics PCBs, automotive parts, payment slips and postal items.
- Category
- Matrix
- Symbol
- Matrix (2D) modules
- Data
- Any text within the symbol’s capacity — URLs, numbers or plain text
- Example
- JGB 01Z999999900000001EC1A1AA1A0SN35TQ
Data format
Any text works, including URLs, numbers and Unicode where the symbology supports byte mode. The encoder enforces the capacity of the symbol you configured — shrink the error-correction level or let the size grow if your payload is long.
Strengths and limitations
Strengths
- Stores far more data than a 1D barcode — URLs, IDs or full text payloads.
- Built-in error correction keeps a partially damaged or obscured symbol readable.
Limitations
- Needs a camera-based reader (imager or phone); red-laser-only checkouts cannot read it.
- Print quality and contrast matter more — poor prints fail more often than large 1D bars.
Generate one in QrDeco
- Open QrDeco and choose Royal Mail 2D Mailmark from the format list.
- Type or paste your data — for example JGB 01Z999999900000001EC1A1AA1A0SN35TQ.
- Adjust size, colours, quiet zone or human-readable text in the style panel if you need them.
- Export an SVG or PDF for print, or a PNG for screens — generated locally in your browser, nothing is uploaded.
Scanning and printing tips
- Keep the quiet zone clear on all four sides — it is part of the symbol, not margin.
- Use strong dark/light contrast and never print modules and background in the same ink.
- Choose an error-correction level or symbol size with headroom if the code will be handled, worn or partly covered.
- Export vector output (SVG/PDF) so module edges stay crisp at any print size.
Related formats
More from the Matrix family, plus the family overview: