QR code guide

A QR code is a grid of information. Your camera finds its corners, reads the pattern, and reconstructs the content—even when some data is damaged.

Space is part of the code.

Keep the clear white border around your QR. QR puli reserves at least four modules of quiet space, so a scanner can separate it from its surroundings.

Dark on light wins.

Use strong contrast between your pattern and background. We require a conservative 4.5:1 contrast ratio for export; this is our design guardrail, not a QR standard.

Test the real thing.

We decode the rendered design before download. Paper, glare, distance, and camera quality still matter. Start around 30 mm wide and test at the actual size and distance.

Your code is yours.

There is no built-in expiry or scan limit. Keep linked pages and files available. Create a new QR code if you change its link or details.

A small logo. A lasting impression.

We use high error correction and a restrained logo area. Error correction protects data, but it is not permission to obscure 30% of the image. Every edited design gets checked again.

Use the editor your way.

Use the skip link to reach the editor, Tab to move through controls, and arrow keys within grouped choices. Press Escape to close a dialog. Every color also has a text field for entering a hex value. Selected choices are highlighted and have an accessible selected state. The preview updates automatically, and animations respect your device’s reduced-motion setting.

A closer look at QR codes

QR means Quick Response

QR stands for Quick Response: fast reading was a central goal of the design.

DENSO WAVE

Developed for factories

DENSO introduced QR codes in Japan in 1994, and the automotive industry used them to track parts long before restaurant menus.

DENSO WAVE

A team of just two

Masahiro Hara led a two-person development team, with about a year and a half of work before the QR code was ready.

DENSO WAVE

Three corners reveal the orientation

The three large corner patterns help a reader locate a regular QR code and recognize its orientation, even when it is rotated.

DENSO WAVE

A distinctive recognition pattern

Across the center of a finder pattern, the dark and light widths follow a 1:1:3:1:1 ratio, chosen because it was uncommon in printed material.

DENSO WAVE

There are 40 grid sizes

Regular QR codes range from 21 by 21 modules to 177 by 177, with each version adding four modules per side.

DENSO WAVE

More text can mean more dots

Data type, content length and error correction all affect the grid size; shorter content can produce a less dense code.

DENSO WAVE

Capacity depends on the data

The largest regular QR code at the lowest error correction level can hold up to 7,089 digits, but only 2,953 bytes of binary data.

DENSO WAVE

An international standard since 2000

QR Code became an ISO standard in June 2000, giving makers and readers a shared technical specification.

DENSO WAVE

Micro QR is a different format

Micro QR uses just one finder pattern and starts at 11 by 11 modules, but it is a separate format and needs a compatible reader.

DENSO WAVE

QR codes and music CDs

QR codes use Reed–Solomon error correction, also used on music CDs, to help recover damaged data.

DENSO WAVE

Technical references: DENSO WAVE · Quiet zones · Error correction