How to use QR code

QR code na grid of information. Your camera go find its corners, read the pattern, and pull the content out—even if some data don spoil.

Space dey inside the code.

Keep that clear white border around your QR. QR puli dey reserve at least four modules of quiet space, so scanner go fit separate am from wetin dey around am.

Dark color for top of light color dey work pass.

Make sure say your pattern and background get strong contrast. We need at least 4.5:1 contrast ratio for export; na our design rule be this, no be QR standard.

Test the real thing.

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

Your code na your own.

No expiry date or scan limit dey inside di code. Make sure say di pages and files wey e link to still dey available. Create new QR code if you change di link or details inside am.

Small logo. Big impression.

We dey use high error correction and small logo area. Error correction dey protect data, but e no mean say you fit hide 30% of the image. Every design wey person edit dey get check again.

Use the editor as you like am.

Use the skip link reach the editor, use Tab to move through controls, and use arrow keys for grouped choices. Press Escape to close dialog. Every color get text field to enter hex value. The ones wey you pick go get highlight and accessible selected state. The preview dey update automatically, and animations go follow your device reduced-motion setting.

Make we look QR codes well

QR mean Quick Response

QR stand for Quick Response: dem design am so e go fit read fast-fast.

DENSO WAVE

Dem develop am for factories

DENSO introduce QR codes for Japan for 1994, and automotive industry dey use am track parts long before restaurant menus.

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Team of only two people

Masahiro Hara lead two-person development team, dem work for about one year and half before QR code ready.

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Three corners go show how e dey face

The three big corner patterns dey help reader find regular QR code and know how e dey face, even if e don rotate am.

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One pattern wey people fit easily recognize

For the middle of finder pattern, the dark and light widths dey follow 1:1:3:1:1 ratio, because dem pick am since e no dey common for printed material.

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The grid sizes dey 40

Normal QR codes dey start from 21 by 21 modules go up to 177 by 177, and every version dey add four modules for each side.

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If text plenty, dots go plenty too

Data type, how long the content be, and error correction all dey affect the grid size; if the content short, the code no go too heavy.

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Capacity depend on the data

The biggest regular QR code for the lowest error correction level fit carry up to 7,089 digits, but only 2,953 bytes of binary data.

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E don be international standard since 2000

QR Code turn ISO standard for June 2000, which give makers and readers one common technical specification.

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Micro QR na different format

Micro QR dey use only one finder pattern and e dey start from 11 by 11 modules, but na separate format and e need reader wey fit read am.

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QR codes and music CDs

QR code dey use Reed–Solomon error correction to help recover data wey don spoil. Na this same method dem dey use for music CD too.

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Technical references: DENSO WAVE · Quiet zones · Error correction