rMQR

Overview

The Rectangular Micro QR Code (rMQR Code) is a matrix-type two-dimensional barcode developed by Denso Wave as a rectangular variant of the QR Code, intended for printing in long, narrow spaces where a conventional square QR Code or Micro QR Code would not fit [3] [4]. It retains the QR Code's positioning structure and Reed–Solomon error correction but trades the square aspect ratio for a flat, elongated footprint, making it suitable for cables, instruments, narrow labels, and small components [4]. It was internationally standardised as ISO/IEC 23941:2022 [1].

History

Denso Wave announced the rMQR Code on 25 May 2022 [4]. The company developed it in response to the spread of IoT and the manufacturing need for individual management of ultra-small electronic components, where limited margin space had previously prevented codes from being printed and so hampered information management [4]. The same month, the symbology obtained ISO approval, becoming ISO/IEC 23941:2022 — "Information technology — Automatic identification and data capture techniques — Rectangular Micro QR Code (rMQR) bar code symbology specification" — enabling royalty-free worldwide use [1] [3] [4]. ISO/IEC 23941:2022 specifies the rMQR symbology characteristics, encoding, symbol structure, dimensions, print-quality requirements, error correction, and decoding [1].

Technical specification

Module / symbol structure. rMQR reduces the QR Code's three large finder patterns to a single full finder pattern in the top-left corner plus a smaller finder sub-pattern in the bottom-right corner, which is what allows the rectangular, narrow shape [2] [3]. Denso Wave describes this as reducing the finder patterns "from three to one and a half" [3]. The symbol also includes alignment patterns and timing patterns to detect distortion during reading [2] [3].

Available sizes. rMQR defines 32 sizes (versions), identified from R7×43 to R17×139 [2]:

• Heights (vertical modules): 7, 9, 11, 13, 15, 17 [2]
• Widths (horizontal modules): 27, 43, 59, 77, 99, 139 [2]

The smallest practical symbol stores a minimum of 12 digits in a 7-module-high by 43-module-wide form; the largest is R17×139 [3].

Error correction. rMQR offers two Reed–Solomon error-correction levels — M (~15% recovery) and H (~30% recovery) — using the same Reed–Solomon scheme as standard QR Code [2].

Data capacity (maximum, R17×139). [2] [4]

• Numeric: 361 digits
• Alphanumeric: 219 characters
• Byte: 150 characters
• Kanji: 92 characters

The symbology supports Latin-1, Kanji (Shift-JIS), and GS1-formatted data [2] [4].

Use cases

Denso Wave positions rMQR for part traceability in factories and supply chains, individual management of small electronic and IoT components, brand/design-sensitive products, and information management on slips and forms; specific examples cited include medical device and pharmaceutical labelling and manufacturing price tags [4]. Its flat, elongated shape suits narrow or thin workpieces such as cables, instruments, and narrow labels where a square symbol cannot fit [3]. Reported applications also include package tracking, retail goods identification, document processing, transit ticketing, and healthcare identification [2].

Implementations

• rmqrcode-python (OUDON) — Python; ~181 stars; active in 2026. A dedicated Rectangular Micro QR Code generator in Python [5].
• libqrean (kikuchan) — C; ~101 stars; active 2024. A portable QR and barcode generation/manipulation library that includes rMQR [6].
• qrqrpar (Nakanishi123) — Rust; ~21 stars; active 2025. A QR code generator supporting rMQR, written in Rust [7].
• Zint — C; ~771 stars; active in 2026. The general-purpose Zint library lists rMQR among its supported 2D symbologies [8].

Comparison

rMQR fills the gap between the standard square QR Code (large, square footprint, very high capacity) and Micro QR Code (small but limited capacity), offering both compact size and a larger capacity than Micro QR in a rectangular shape [3]. Against 1D linear barcodes, rMQR stores far more data in a comparably narrow strip, making it a candidate replacement for 1D codes on cables and instruments where vertical space is scarce [4]. Compared with the full QR Code, its capacity is much smaller — 361 numeric characters at most versus the QR Code's maximum of about 7,089 numeric characters [4]. It uses only two error-correction levels (M and H) rather than QR Code's four (L, M, Q, H) [2].

Fun facts

• rMQR achieves its rectangular shape by cutting the QR Code's three finder patterns down to "one and a half" — a single full finder plus a small sub-pattern — which Denso Wave highlights as the key structural change [3].
• Within a year of release, rMQR had already attracted security-research attention: open repositories host thousands of deliberately malicious rMQR codes for penetration-testing red-team use [2].

Status

Active and current. rMQR is an international standard, ISO/IEC 23941:2022, and is royalty-free for worldwide use [1] [3].

Sources

1 ISO/IEC 23941:2022 — Rectangular Micro QR Code (rMQR) bar code symbology specification — ISO, 2022 2 Rectangular Micro QR Code — Wikipedia, 2026 3 rMQR Code — QRcode.com / Denso Wave, 2022 4 DENSO WAVE Develops "rMQR Code" — Denso Wave, 2022 5 rmqrcode-python — OUDON / GitHub, 2026 6 libqrean — kikuchan / GitHub, 2024 7 qrqrpar — Nakanishi123 / GitHub, 2025 8 Zint barcode encoding library — Zint Project / GitHub, 2026

Deployments

No country reports mention this standard by name.

Regions / aggregations not mapped to a single country

• Universal