QR Code Types Explained: Model 2, Micro QR, rMQR and Other Variants
Published 21 October 2026 by the QRCodeBarn team.
Almost every QR code you scan on a menu, poster or parcel is the same type: a QR Code Model 2. But it isn't the only kind. Denso Wave, the Japanese company that invented the QR code, has developed several variants for smaller spaces, narrow labels, private data and branded designs. This guide explains what each one is, where you might come across it, and why a standard QR code is still the right choice for almost everything people scan with a phone.
Model 1: the original QR code
The very first QR code, released in 1994, is now called Model 1. Its largest version was Version 14, a grid of 73 × 73 modules (the small squares that make up the pattern), which could hold up to 1,167 digits.
Model 1 worked well on flat labels in factories, but it had a weakness. If the code was printed on a curved surface or photographed at an angle, the grid could distort enough to confuse the reader. You are very unlikely to meet a Model 1 code today. If you are curious about how the QR code started, read the history of the QR code.
Model 2: the QR code everyone uses
Model 2 is the improved design, and it is what people mean by "QR code" today. It is the version set out in the international standard, ISO/IEC 18004, and the one every phone camera is built to read.
The key improvement was the alignment pattern, a small square-within-a-square that appears in the lower right area of all but the smallest codes, with more of them in larger codes. Alignment patterns give the scanner extra reference points, so it can correct for curves and odd angles. Model 2 also goes much bigger, up to Version 40, a grid of 177 × 177 modules that can hold up to 7,089 digits.
Model 2 codes come in 40 sizes and four error correction levels (L, M, Q and H), which let the code survive damage or a logo in the middle. Our guide to QR code error correction explains how to choose a level, and how QR codes work explains what each part of the pattern does.
Micro QR Code: for very small spaces
A standard QR code needs three large finder squares in its corners and a blank margin, called the quiet zone, at least four modules wide all round. On a tiny electronic component, that overhead takes up a lot of room.
Micro QR Code solves this by using only one finder pattern and needing a quiet zone of just two modules. It comes in four sizes, from M1 (11 × 11 modules) to M4 (17 × 17 modules).
The trade-off is capacity. The largest Micro QR code holds at most 35 digits, or about 21 letters and numbers, which is less than the smallest standard QR code. That is too short for most web addresses. The smallest size, M1, holds only numbers and can detect errors but not correct them.
Micro QR codes are mainly used for marking small parts, circuit boards and components in manufacturing. They were approved as a Japanese Industrial Standard in 2004. Many phone camera apps don't read them, so they are not a good choice for anything aimed at the public.
rMQR Code: the rectangular QR code
rMQR stands for rectangular Micro QR Code. As the name suggests, it is a long, thin rectangle rather than a square, designed for places where there is height for only a narrow strip, such as the edge of a printed circuit board, a test tube, a cable or a thin label.
According to Denso Wave, rMQR uses the equivalent of one and a half finder patterns instead of three, and comes in a wide range of sizes. The smallest is 7 modules high by 43 wide and stores at least 12 digits. The largest is 17 modules high by 139 wide and stores up to about 361 digits. It was approved as an international ISO standard in 2022.
Like Micro QR, rMQR is aimed at industry and laboratories using dedicated scanners. Support in everyday phone apps is limited, so test with the actual devices that will read it before relying on it.
SQRC: a QR code with a private section
SQRC is a QR code with a reading restriction. It looks exactly like an ordinary QR code, and its public part can be read by any scanner, but it can also carry a second, private part that only a reader with the right key can decode.
Businesses use this kind of code for things such as internal records, staff identification and documents where some information should be visible to everyone while some is kept confidential. A normal phone sees only the public content.
FrameQR: a QR code with a picture window
FrameQR is a QR code with a "canvas area" in the middle, where a logo, picture or text can be placed by design. With an ordinary QR code, putting a logo in the centre means covering some of the data and relying on error correction to recover it. FrameQR reserves the space instead.
Denso Wave suggests uses such as promotions and checking that a product is genuine. FrameQR needs compatible reading software, so for a code that customers will scan with their own phones, a standard QR code with a carefully sized logo is the safer option. See our guide to making a QR code with a logo.
Comparison table
| Type | Shape | Finder patterns | Largest size | Max numeric capacity | Phone camera support |
|---|---|---|---|---|---|
| QR Code Model 1 | Square | 3 | 73 × 73 | 1,167 digits | Rarely used today |
| QR Code Model 2 | Square | 3 | 177 × 177 | 7,089 digits | Universal |
| Micro QR Code | Square | 1 | 17 × 17 | 35 digits | Limited |
| rMQR Code | Rectangle | 1.5 (equivalent) | 17 × 139 | About 361 digits | Limited |
| SQRC | Square | 3 | As Model 2 | Public part as Model 2 | Public part only |
| FrameQR | Square with canvas | 3 | Varies | Varies | Needs compatible software |
Capacities are the maximums published by Denso Wave and the QR code standard. Real codes usually hold much less.
A note on the name
"QR Code" is a registered trademark of Denso Wave. Denso Wave chose not to enforce its patent on the standard QR code, which is a big reason the format spread so widely and why anyone can create a QR code for free. The company also says it has waived its patent rights for Micro QR. Other formats, such as SQRC and FrameQR, are Denso Wave's own products.
Which type should you use?
For almost every everyday job, use a standard QR Code Model 2. It is what free generators, including ours, create, and it is what every iPhone and Android camera reads. That covers menus, posters, business cards, WiFi logins, review links, event tickets and product packaging.
Consider the other types only if you are marking tiny or narrow industrial items and will read them with dedicated scanners (Micro QR or rMQR), or if you have a specialist need for private data or a built-in design area and control the scanning software (SQRC or FrameQR).
If your standard code feels too big for the space, there are usually simpler fixes than switching format. Shorten the web address so the code needs fewer modules, choose a lower error correction level if there is no logo, and check our QR code size guide for the minimum print size.
Frequently asked questions
What is the most common type of QR code?
QR Code Model 2. It is the type defined in ISO/IEC 18004 and the one every smartphone camera reads. When people say "QR code", this is what they mean.
Can my phone read a Micro QR code?
Sometimes, but not reliably. Many built-in camera apps only look for standard QR codes. Micro QR and rMQR codes are mainly read with industrial or specialist scanners.
What is the smallest type of QR code?
Micro QR Code. Its smallest version is 11 × 11 modules with a two-module margin, compared with 21 × 21 modules and a four-module margin for the smallest standard QR code.
Is a rectangular QR code a real QR code?
Yes. The rMQR Code is a rectangular member of the QR code family, developed by Denso Wave and approved as an ISO standard in 2022. It is designed for narrow spaces rather than for scanning with phones.
Which type of QR code does QRCodeBarn make?
Our free QR code generator creates standard QR Code Model 2 codes, which work with any phone camera. They are static codes, so they keep working as long as the destination does. Learn more in static vs dynamic QR codes.
This article was drafted with AI assistance and reviewed for accuracy. Read our editorial policy and AI content policy.