The difference in one sentence
A linear barcode encodes a short string of digits as bars of varying width, read across in one direction. A QR code encodes data in two dimensions, as a grid of black and white squares, read across and down at once. Denso Wave, the company that announced the QR code in 1994, describes the limit it was built to overcome: a barcode holds about 20 alphanumeric characters, while the new code could hold about 7,000 numerals, plus Japanese kanji. The QR code is therefore not a replacement for the barcode so much as a different tool: the barcode is a tiny label for a database lookup, the QR code is a carrier for the data itself.
Capacity, size and damage
| EAN-13 / UPC-A barcode | QR code | |
|---|---|---|
| Holds | 13 digits (EAN-13) or 12 digits (UPC-A); EAN-8 holds 8 for small packages | Up to 7,089 digits, 4,296 letters and digits, 2,953 bytes or 1,817 kanji at the largest size with the lowest error correction |
| Typical content | A product number (GTIN) that a till looks up in its database | A web address, Wi-Fi credentials, a contact card, a ticket or payment token, plain text |
| Read by | Laser and imaging scanners at the checkout; phone apps with a lookup | Phone cameras, imaging scanners |
| Orientation | Must be scanned along the bars | Readable from any direction in 360° |
| Damage | A check digit (modulo 10) detects a misread; a damaged bar means no read | Built-in error correction restores about 7, 15, 25 or 30 percent of the codewords (levels L, M, Q, H) |
| Sizes | One format per symbology; the bars need a quiet zone on each side | 40 versions from 21 × 21 to 177 × 177 modules; more data means a denser grid |
| Needs registration? | Yes for retail: the number comes from GS1 | Only if it identifies a product for sale; otherwise none |
The 13 digits of an EAN-13 are a GS1 prefix, a manufacturer code, a product code and a check digit computed modulo 10 with alternating weights of 3 and 1, which catches every single-digit scanning error. The barcode generator computes that check digit for you and lets you set the quiet zones so the code scans. A QR code's error correction is a different idea: it adds redundant codewords so the reader can reconstruct the data even when part of the symbol is missing, which is what makes a logo in the middle possible.
Products for sale: barcode, and a QR code on the way
If the item will be scanned at a checkout, it needs a GS1 identification number encoded as an EAN-13 (most of the world) or a UPC-A (North America). The number is what the retailer's system recognises; the barcode is just its printed form. A made-up number is useless at the till, because the retailer's database does not know it. The barcode generator's page explains when a GS1 membership is required.
That picture is changing. GS1 US calls Sunrise 2027 a transition from 1D UPC barcodes to 2D barcodes at retail: point-of-sale scanners should be able to read a QR code written in the GS1 Digital Link syntax, or a GS1 DataMatrix, and extract the GTIN from it. Its advice to brands is to add a 2D code to existing packaging first, carrying the same GTIN as the UPC, and to add more data such as batch or expiry dates later. For now, a product needs the linear barcode; a GS1 Digital Link QR code next to it is the forward-looking extra, not a replacement.
Menus, posters, tickets, Wi-Fi: QR code
Anything meant for a phone is a QR code question. A menu is a link to a page; a poster carries a link with tracking parameters; a Wi-Fi code carries the network name and password in a format phones understand; a ticket carries a token the venue checks against its list. None of these needs registration, and the QR code generator has a type for each. Three practical rules:
- Keep the content short. The grid grows with every character. A short link (a redirect you control) scans at a smaller size and from further away than a 200-character URL with tracking parameters.
- Pick the error correction for the surface. Denso Wave's guidance: Level M for ordinary use, Q or H where the code will get dirty or scratched, L only for clean screens with a lot of data. A logo over the centre costs error-correction budget, so pair it with Q or H.
- Test it printed, at the real size, with several phones before ordering a thousand table tents. Contrast matters more than colour: dark modules on a light background, and a clear margin all round.
Inventory, assets and documents: either
Inside a company nobody's database is involved except your own, so both work and the choice is about the readers you have. Older scanners built for linear codes read only those; imaging scanners and phones read both. A linear Code 128 barcode holds a short asset number and prints well on a label printer; a QR code can carry the whole record, a serial number and a link to the manual, and survives a scuffed label better. Many teams print both on the same label until every scanner in the building can read 2D.
Which one, in short
| Use | Pick | Why |
|---|---|---|
| Product sold in shops | EAN-13 or UPC-A barcode from a GS1 number | Checkouts look up the number; a 2D code is the future add-on |
| Restaurant menu, poster, flyer | QR code with a link | Phones open it directly, no app |
| Event or transport ticket | QR code (or the format the venue's scanner expects) | Carries the token itself, tolerates a creased printout |
| Wi-Fi for guests | QR code, Wi-Fi type | Phones join the network from the camera |
| Shelf labels, internal assets | Barcode if your scanners only read linear codes, QR otherwise | Match the reader you already own |
| Business card, contact details | QR code, vCard type | A barcode cannot hold a name and number |
Frequently asked questions
Is a QR code a barcode?
Yes, a two-dimensional one. A traditional barcode stores data in one direction, as bars of different widths; a QR code stores it both across and down, as a grid of squares, which is why it holds so much more. Both are read optically, but a QR code needs an imaging reader such as a phone camera.
Can a phone scan a regular barcode?
Many phone camera apps read QR codes directly, and scanner apps read EAN and UPC barcodes too. What the phone does with the result differs: a QR code with a web address opens the page, while a product barcode only gives you the 12 or 13 digit number, which an app then has to look up.
Do I need a GS1 number for a QR code?
Not for a menu, a ticket, a Wi-Fi code or a link on a poster; any QR code generator works and nothing has to be registered. You need a GS1-issued number only when the code identifies a product for retail sale, whether it is a UPC barcode or a QR code that follows GS1 Digital Link and carries the product's GTIN.
Which error correction level should I pick for a QR code?
Level M, which restores about 15 percent of damaged codewords, is the usual choice and the one Denso Wave says is selected most often. Use Q (25 percent) or H (30 percent) when the code will get dirty or scratched, or when you put a logo over the middle. Use L (7 percent) only for clean screens with a lot of data, because every step up makes the code denser.
Will product barcodes be replaced by QR codes?
GS1 US calls Sunrise 2027 a transition from 1D UPC barcodes to 2D barcodes at retail, with point-of-sale scanners able to read a QR code or a GS1 DataMatrix and extract the product number. Its own advice to brands is to add a 2D code to existing packaging rather than remove the UPC, so for the near future products carry both.
Sources
- Denso Wave: History of the QR Code (announced in 1994; a barcode holds about 20 alphanumeric characters, the QR code about 7,000 numerals and kanji)
- Denso Wave: About the QR Code (readable from any direction, self-correcting when partly damaged; versions 1 to 40, 21 × 21 to 177 × 177 modules)
- Denso Wave: Error correction feature (Level M at 15 percent is chosen most often; Q and H for dirty environments, L for clean ones)
- Wikipedia: QR code (capacity of a version 40 code: 7,089 numeric, 4,296 alphanumeric, 2,953 bytes, 1,817 kanji; error correction L 7%, M 15%, Q 25%, H 30%; ISO/IEC 18004)
- Wikipedia: International Article Number (EAN-13 has 13 digits, extends the 12-digit UPC-A, EAN-8 for small packages, modulo-10 check digit)
- GS1 US: Sunrise 2027 (transition from 1D UPC barcodes to 2D barcodes, QR codes with GS1 Digital Link and GS1 DataMatrix, add 2D codes to existing packaging)
General information based on the sources above, not tax, legal or financial advice.