QR code basics

What a QR code is, how it works, why you would use one, and the cases where you shouldn't.

• Are QR codes dead?No - the obituaries were written around 2012, and what changed since is specific. Native camera scanning arrived in 2017 and payments adopted QR at scale.
• Are QR codes patented and free to use?Denso Wave holds the original patents but pledged not to enforce them for standard use - and the 1994 patents have expired anyway. The name is trademarked.
• Do QR codes cost money?The format is free and static codes cost nothing to generate, forever. Money enters with dynamic redirects, analytics dashboards, design tools and print.
• Do QR codes expire?A static QR code never expires: the destination is encoded in the pattern, so nothing has to keep running. A dynamic QR code expires when the provider's…
• How do QR codes work?A scanner finds the three corner squares, works out the code's grid and orientation, samples every cell as black or white, reads the format bits to learn…
• How many people scan QR codes?Nobody knows precisely, and that is by design - static QR codes leave no record when scanned. What can actually be measured, and how to reason about it.
• ISO/IEC 18004: the QR code standard explainedWhat the QR standard defines across its 2000, 2006, 2015 and 2024 editions, what it deliberately leaves out, and what implementers actually need from it.
• Micro QR codes: the small variant and its big trapMicro QR shrinks the format to four sizes from 11 x 11 modules with one finder pattern - but most phone cameras cannot read it, which rules out consumers.
• QR code adoption statistics: what is actually knownMost QR statistics are vendor marketing. Here is what is verifiable - native scanning since 2017, UPI past 10 billion monthly payments, and Sunrise 2027.
• QR code benefits and drawbacksThe honest case for and against QR codes - free and universally scannable since 2017, but smartphone-dependent, uneditable once printed, and easy to abuse.
• QR code licensing and trademark: what you must creditThe pattern needs no licence, but "QR Code" is a Denso Wave trademark with a requested credit line. What to write on packaging, apps and publications.
• QR code vs short linkThey solve different halves of the same problem and work best combined - a short URL inside a QR code produces a coarser pattern that scans more easily.
• rMQR: the rectangular Micro QR coderMQR (ISO/IEC 23941, 2022) reshapes QR into strips from 7 to 17 modules tall, holding up to 361 characters - ideal geometry, but scanner support is sparse.
• Static vs dynamic QR codesA static QR code contains its destination directly, so it never expires and cannot be tracked or edited. A dynamic code contains a short link that…
• The economics of free QR code generatorsServing a static QR generator costs almost nothing, which is why so many exist. The expensive part is dynamic infrastructure - and the funnels that fund it.
• What is a QR code?A QR code is a two-dimensional barcode that stores data as a grid of black and white squares. A camera reads the pattern and recovers the original text.
• When not to use a QR codeDo not use a QR code where the audience is moving, where a tappable link already exists, where it would be the only route to essential information, or…
• Who invented the QR code?Masahiro Hara led the two-person Denso team that invented the QR code in 1994. The grid layout came to him while playing Go at lunchtime.
• Who pays when a QR code is free?Someone always covers the cost. The five funding models behind free QR tools, and the thirty-second decode test that reveals which one you are inside.
• Why use a QR code?A QR code is worth using when it removes typing at a moment when typing is the obstacle: joining WiFi, paying at a counter, opening a menu, saving a…
• Are QR codes still relevant?Yes, and more so than during the pandemic peak. The difference is that usage has shifted from menus to payments, packaging and identity: UPI in India and…
• FrameQR: a reserved canvas instead of a buried logoFrameQR is Denso Wave's format with a designed-in canvas area for images - a cleaner mechanism than hiding logos under error correction, but proprietary.
• iQR codes: Denso Wave's high-capacity proprietary variantiQR is a proprietary Denso Wave format - square or rectangular, about 80% more data in the same area, up to roughly 40,000 digits - but phones cannot read it.
• Model 1 vs Model 2 QR codesModel 1 is the original 1994 QR code, capped at version 14 with no alignment patterns. Model 2 extends to version 40 and is the only kind generated today.
• QR code vs Aztec codeAztec codes need no quiet zone and centre their finder, which suits cramped boarding passes and rail tickets. QR wins capacity and universal phone support.
• QR code vs barcodeA traditional barcode stores about 20 characters in one dimension and must be scanned in roughly the right orientation. A QR code stores up to 2,953 bytes…
• QR code vs Data MatrixBoth are 2D matrix codes. Data Matrix marks smaller and needs only a one-module quiet zone, which is why pharma uses it. QR wins capacity and phone support.
• QR code vs MaxiCodeMaxiCode is UPS's fixed-size hexagonal sortation code - about 25 x 25 mm, 93 characters, a central bullseye. Outside parcel conveyors, QR wins every time.
• QR code vs NFCA QR code is printed and costs nothing per item; NFC needs a chip in every object and costs cents to dollars each. NFC is faster and needs no camera, but…
• QR code vs PDF417PDF417 is a stacked linear barcode from 1991, still mandated on US driving licences and printed boarding passes. QR stores the same data in far less space.
• QR codes after COVID: what stuck and what recededThe pandemic made scanning a habit through menus, check-ins and certificates. Check-ins vanished, PDF menus receded, and payments and ticketing kept growing.
• QR codes around the world: one symbol, many dialectsThe square is identical everywhere; the payload is not. UPI in India, PIX in Brazil, EMVCo across Southeast Asia, EPC in Europe - a map of the ecosystems.
• SQRC: the QR code with a private compartmentSQRC is Denso Wave's split-payload format - a public part any scanner reads, plus a private part only keyed readers decode. Not encryption for the public web.
• The history of QR codesQR codes were invented in 1994 by a team led by Masahiro Hara at Denso Wave, a Toyota subsidiary, to track car parts faster than barcodes allowed. Denso…
• Why QR codes took off in Asia firstJapan had QR-reading phones by 2002 - fifteen years before iPhones scanned natively. Culture, kanji mode and China's payment leapfrog did the rest.