What size should a printed QR code be?

A rule of thumb for size

A common guide is that the distance people scan from should be about ten times the width of the code. A code held in the hand at arm's length can be small. A code on a wall that people read from across a room needs to be much bigger.

• Held in the hand (business card, flyer, table tent): at least about 2 cm (0.8 inches) wide, and 3 to 4 cm is more comfortable.
• About a metre away (shop window, counter sign): around 10 cm.
• Several metres away (poster, banner): scale up in the same proportion, then test it.

These are guides, not guarantees. Phone cameras, lighting and how complex your code is all change what works, so always test.

Keep the white border

Phones use the empty space around a code to find where it starts. Leave a clear border of at least four small squares on every side, and do not let text or pictures run into it. The generator's "White border" setting does this for you.

Colours and contrast

• Dark code on a light background is the most reliable.
• Avoid light-on-dark and low-contrast pairs such as yellow on white. The generator warns you about these.
• A photo behind the code makes it harder to read. Use a plain background.

Printing

• For print, download the SVG or PDF. They stay sharp at any size. If you must use a PNG, choose the largest size.
• Do not stretch the code. It must stay perfectly square.
• Shorter links make simpler codes with bigger squares, which scan more easily at a given size.
• Glossy or curved surfaces cause glare and distortion. Matte paper on a flat surface is safest.

Always test the real thing

Print one at the actual size, in the actual place, and scan it with at least two different phones in the lighting people will really have. Fixing a problem takes a minute now; after printing a thousand, it is expensive.