Printing QR codes
Print once, scan for years.
Here are some best practices for printing QR codes. The goal is not to have to re-print codes, so print a test page and follow these tips before your final print.
Print a test page to determine the right size for your use case
Real PermaPath codes from ½ inch to a full page, with how far away each one scans. A credit-card outline, coins and a ruler show whether your printer printed at the right size.
Opens a PDF. Print it at 100% or “Actual size”, not “Fit to page”.
Size guidelines
- The 10x rule of thumb. A 1 inch code can be scanned from 10 inches away. A 1 foot code can be scanned from 10 feet away.
- ¾ inch (2 cm) is a comfortable minimum for things held in the hand, like stickers, tags and labels. ½ inch works on newer phones, but some older ones struggle.
- Go bigger for signs. 3–4 inches on a poster or window, 6 inches or more for anything read across a room or from the street.
Make it easy to scan
- Keep the white border. The quiet space around the code is part of it. Don’t crop it, and don’t place the code right against an edge, a busy background or other print.
- Dark on light. Black on white is safest. Colors are fine if the code is much darker than its background. Don’t invert it to light on dark; some phones won’t read that.
- Flat and matte. Glossy finishes and laminate can glare under lights. A tight curve, like a narrow bottle, can distort the code; put it on the flattest spot.
- Say what it’s for. A few words next to the code, like “Scan for the menu”, get far more scans than a code alone.
- Test before printing a lot. Print one, scan it with an iPhone and an Android phone from the distance people will actually be at, then print the rest.
Stickers and labels
- Download the SVG for print shops and design tools: it stays sharp at any size. The PNG is fine for home printing up to about 8 inches.
- Many codes at once: create them in a batch, export the CSV, and use its qr_url column with a label tool that makes QR codes from a spreadsheet, such as Avery’s.
- Indoors, paper labels are fine. Outdoors or on things that get wet, use waterproof vinyl stickers, ideally with a UV-resistant laminate, or engraved or etched metal for plaques.
- Engraving and etching work well when the marks are deep and clean. Make the code larger than you would print it, at least 1 inch, and test one first.
- Print before you know the destination: a batch of codes can go on stickers now and be pointed somewhere later.
Why PermaPath codes are a little denser
A PermaPath code holds a full permanent address on Arweave, about 110 characters, so it has a few more squares than a code for a short link. That’s what lets it keep working even if PermaPath disappears. In practice it only matters below about ¾ inch; the test page shows exactly where your phone stops reading them.