# iQR codes: Denso Wave's high-capacity proprietary variant

> iQR is a proprietary Denso Wave format, not part of ISO/IEC 18004. It comes in square and rectangular versions, packs about 80% more data than a QR code of the same size, and reaches roughly 40,000 numeric characters - but only Denso-compatible industrial readers decode it, so phones cannot.

Source: https://useqr.app/docs/basics/iqr-code · Last reviewed 2026-08-21 · UseQR is free forever, no signup.

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## What iQR is

iQR is a later [Denso Wave](/glossary/denso-wave) development that reworks the QR matrix
for density and flexibility rather than universal readability. Unlike standard QR, Micro
QR and rMQR, it was never submitted as an international standard: it is proprietary
technology, generated and decoded with Denso Wave software and readers.

According to Denso Wave's published specifications, the headline gains over standard QR
are:

- **Same area, ~80% more data**, a tighter internal layout spends fewer modules on
  overhead.
- **Same data, ~30% smaller symbol**, useful when label space is the constraint.
- **Square or rectangular formats**, like [rMQR](/docs/basics/rmqr-rectangular-micro-qr)
  but within one family, suiting strip-shaped labels and cylindrical parts.
- **A far higher ceiling**: the largest iQR symbols store roughly **40,000 numeric
  characters**, more than five times standard QR's 7,089 ceiling.
- **Turned-over reading**: iQR can be printed black-on-white or inverted and read either
  way, and supports direct part marking such as dot peening, where standard QR's
  [polarity rules](/docs/spec/qr-code-color-inversion-and-polarity) are stricter.

## The trade nobody should miss

Every one of those gains is paid for in reader support. No phone camera reads iQR. No
mainstream open-source library decodes it. The format lives entirely inside ecosystems
built on Denso reading hardware and SDKs: automotive plants, parts logistics, industrial
traceability systems, the world QR itself [was born in](/docs/basics/history-of-qr-codes).

This is the structural difference between the open family and the proprietary one. When
Denso released standard QR it [declined to enforce its patents](/docs/basics/are-qr-codes-patented-and-free-to-use),
and the format became universal infrastructure. iQR, like [SQRC](/docs/basics/sqrc-secure-qr)
and [FrameQR](/docs/basics/frame-qr), is the other business model: capability sold with
the hardware to read it. Neither model is wrong, but they produce opposite answers to
"who can scan this?"

## When you would actually meet one

Realistically: on a factory floor or in a parts supply chain already running Denso
scanners, where an engineer chose iQR because a label had to hold a full traceability
record in a space standard QR could not manage. If that is your environment, the format
does what it claims, and your scanner vendor's documentation is the authority.

If you are choosing a format for anything else, the decision is straightforward:

- **Public will scan it** → standard QR, nothing else.
- **Narrow label, your own scanners, open tooling preferred** → rMQR, the standardised
  rectangular option.
- **Extreme data density, Denso hardware already deployed** → iQR is the one scenario
  where it is the right call.

There is no free generator for iQR and cannot usefully be one, a symbol only Denso
readers decode has no life outside those deployments. For every open format,
[verification before printing](/docs/developers/why-verify-that-your-qr-code-decodes)
remains the habit that catches problems early.

## FAQ

### What is an iQR code?
iQR is a proprietary matrix code from Denso Wave, the inventor of QR. It stores about 80% more data than a QR code of equal size, offers square and rectangular formats, and reaches roughly 40,000 numeric characters, but requires Denso-compatible readers.

### Can a phone read an iQR code?
No. iQR is not part of the open ISO standard and stock camera apps do not detect it. It is decoded by Denso Wave reading hardware and software used in industrial systems.

### What is the difference between iQR and QR?
Standard QR is an open ISO/IEC 18004 format readable by any camera; iQR is proprietary, denser, supports rectangular shapes and inverted printing, and holds far more data, at the cost of working only within Denso-equipped environments.

### Should I use iQR for my product labels?
Only if your reading hardware is already Denso-based and you need capacity or shapes standard QR cannot provide. For labels the public or general devices must scan, use standard QR; for narrow industrial labels with open tooling, consider rMQR.

## Try it

- https://useqr.app/text
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