A rectangular variant of the QR code — taller widths than heights from 43×7 up to 139×17 modules — designed for narrow spaces like receipts, labels, and component reels where a square code cannot fit.
rMQR (rectangular Micro QR) is Denso Wave's answer to a mundane but pervasive problem: many real-world surfaces are long and narrow, not square. Receipt headers, shipping label margins, electronic component reels, cable flags, and the edges of circuit boards offer thin rectangular strips where a square QR code simply does not fit. rMQR keeps QR's encoding, error correction, and reader logic but repackages the symbol as a rectangle, with widths always exceeding heights.
Rectangular geometry
rMQR symbols are named R-height×width: from R7×43 (7 modules tall, 43 wide) up to R17×139, with several intermediate sizes. The finder pattern arrangement is adapted to the rectangle — corner markers positioned for the elongated shape — while the data encoding, Reed-Solomon error correction, masking, and format information follow the same principles as standard QR. The quiet zone and high-contrast requirements are unchanged: a rectangle does not relax the optical rules, it only changes the aspect ratio.
Why not just use a smaller square QR?
The alternative to rMQR is shrinking a square QR until it fits the narrow dimension — but that shrinks the data capacity with the square of the size reduction, often below what the payload needs, and produces tiny modules that are hard to print and scan. A rectangular symbol uses the available long dimension fully: an R17×139 code has far more data modules than any square code that fits in a 17-module-tall strip. For the same strip height, rMQR carries several times the payload of the largest square code that fits.
Ecosystem and reader support
rMQR was introduced by Denso Wave in 2022 and subsequently standardized by ISO, which gives it a solid specification foundation. The practical caveat is the same as with Micro QR: reader support lags the standard. Industrial machine-vision libraries have adopted it, but consumer phone camera apps generally do not decode rMQR. Deploy it where the readers are known and controlled — production lines, warehouse scanners, purpose-built apps — and stick with square QR for consumer-facing placements.
Design guidance
Treat rMQR like any QR symbol for print discipline: minimum module widths, 4-module-equivalent quiet zones, dark-on-light contrast, and no styling of the finder or timing structures. The elongated shape actually helps placement on real packaging — a code that runs along the bottom edge of a label is less likely to be covered by handling than a square code floating in the middle. When planning label layouts, consider rMQR early: retrofitting a rectangular strip for a square code late in a packaging design cycle is a common source of quiet-zone violations.
Diagram description: An R7×43 and an R17×139 rMQR symbol beside the largest square QR code that fits the same strip height, showing the rectangular symbol’s far greater data area.