Web & Utilities

QR Code Size Calculator

How big should your QR code be? Enter the scan distance to get the recommended print size (the trusted 10:1 distance‑to‑size rule), in both cm and inches.

The 10:1 distance-to-size rule

The reliable rule of thumb for print is distance ÷ 10 = minimum code width. A poster scanned from 2 metres needs a code at least 20 cm wide; a business card scanned from 30 cm needs only ~3 cm. This calculator does the conversion and gives both cm and inches.

min width = scan distance ÷ 10

Don't forget the quiet zone

Every QR code needs a clear margin — the "quiet zone" — of at least 4 modules around it, or scanners struggle to lock on. Keep the background high-contrast (dark code on light background) and never stretch the code out of square.

How to use this calculator

  1. Enter the scan distance.
  2. Read the recommended print size.
  3. Verify it fits your data load.

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Frequently asked questions

What is the 10:1 rule?

A QR code should be at least 1 unit wide for every 10 units of scanning distance. Scanning from 100 cm away? Make the code at least 10 cm wide.

Does more data need a bigger code?

Yes. More data means more modules (squares), so each module gets smaller at a fixed size. For long URLs or lots of text, increase the size or shorten the data.

What is the 10:1 rule for QR codes?

A QR code should be at least 1 unit wide for every 10 units of scanning distance. To be scanned from 100 cm away, make the code at least 10 cm wide.

Does more data require a bigger QR code?

Yes. More data adds modules (the small squares), so at a fixed size each module shrinks and becomes harder to scan. For long URLs, increase the size or shorten the link.