QR codes on greeting cards

A greeting card is read in the hand at 20–30 cm, so a 2 cm code is enough. The one rule that matters: never let the code cross the fold — a crease through the modules kills the scan. Use error correction M and keep the code inside one flat panel.

Typical scan distance	20–30 cm
Minimum code width	≥ 2 cm
Error correction	M

The numbers

Hand-held reading distance is 20–30 cm, so the ten-to-one rule gives a 2–3 cm code — the same close-range floor as business cards. That fits discreetly on the back panel next to the maker's mark, or inside below the message. There is no reason to go bigger on a card; there is a hard reason never to go smaller than 2 cm on textured stock.

The fold is the failure mode

A greeting card is a folded object, and the crease is a module-destroyer: it shadows a line of the grid, cracks ink along its length, and bends the two halves of the code into different planes. A code that crosses the fold fails all three ways at once, and no error-correction level rescues a code split across two planes.

The rule is absolute: the whole code, plus its four-module quiet zone, stays inside one flat panel. Keep it at least 1 cm from the crease — cardstock bruises beyond the fold line itself, especially on heavy 300 gsm stock that has been scored.

Stock and ink

Greeting cards favour uncoated, textured, or felt-finish stocks, and uncoated paper wicks ink outwards — modules grow and the gaps between them shrink. The mechanics are covered in uncoated paper and ink spread; the practical rules:

Modules ≥ 0.5 mm (a 2 cm version-2 code clears this).
Solid black on cream or white — both clear the 40% luminance-difference floor. Foil, gloss-varnish and letterpress-debossed codes photograph badly; print the code flat.
Proof one card and scan-test it folded, not as a flat sheet.

What a card code is for

The honest case: a QR code should never replace the handwriting — a card exists to carry a human hand, and outsourcing the sentiment to a link defeats the object. The code earns its place carrying what paper cannot:

A video message — the strongest use; a private link to a recorded greeting.
A gift link — vouchers, registries, tickets.
RSVP for the party the card announces (for formal versions, see invitations).

A URL code covers all three. Generate it client-side so a private video link never touches a third-party server.

FAQ

What size should a QR code be on a greeting card?

Two to three centimetres. Cards are read in the hand at 20–30 cm, and the ten-to-one rule makes 2 cm the floor. On textured or uncoated stock, stay at the top of that range so ink spread does not close the gaps between modules.

Can a QR code go across the fold of a card?

No. The crease shadows, cracks and bends the module grid, and a code split across two planes will not decode. Keep the entire code and its quiet zone on one flat panel, at least a centimetre clear of the fold.

What do people put QR codes on greeting cards for?

The three uses that work: a recorded video message, a gift link (voucher, registry, tickets), and an RSVP link. The code should add something paper cannot carry — it should never replace the handwritten message itself.

Will a QR code print well on textured card?

Yes, if the modules are at least 0.5 mm and the ink is solid black. Uncoated and felt stocks spread ink, so avoid fine, dense codes and always test-scan a printed proof of the actual card before the full run.