Iron-on vs DTG vs screen print for QR codes

Three ways to get a code onto a shirt, three very different relationships with a washing machine. This is the honest version: how each method prints, what it does to a QR code's edges and contrast, what it costs, and how hard it is at a kitchen table. Whichever you pick, the rules of a scannable print are the same — big enough modules, real contrast, an empty quiet zone.

Iron-on and heat transfer

How it works. Print the design onto transfer paper with a home printer, or cut it from heat-transfer vinyl, and press it on with an iron or a heat press. DTF transfers — printed film you make or order — are the modern upgrade to the same idea.

Scan reliability. Vinyl is the surprise: crisp, hard edges, exactly what a QR code wants. Inkjet transfer paper is the weak link — fuzzier edges, and ink that sits on a coating, so contrast fades early. DTF sits between the two: a sharp print on a flexible film that holds detail well.

Cost and DIY. The cheapest way in, and the only one that needs no special machine beyond a printer; vinyl wants a cutter. Weeding a vinyl QR code — picking out the tiny negative squares — is fiddly, so print the code big: 3 inches or more.

Wash life. The shortest of the three. Expect transfers to fade or crack somewhere in the 10 to 30 wash range; DTF does better. Fine for an event shirt; risky for a daily driver.

DTG — direct to garment

How it works. A specialised printer inks the shirt directly, the way a paper printer works with better aim. No screens, no setup, one shirt or one hundred.

Scan reliability. Excellent detail, and its slightly soft edges are no problem at sensible sizes — DTG resolves modules cleanly. The trap is contrast: on dark shirts DTG lays a white underbase under the ink, and a thin or under-cured print reads grey on grey sooner than you expect. Give the design contrast headroom.

Cost and DIY. Middle cost per shirt at any quantity, and almost always a service rather than a home method — the printers cost thousands. No setup fees make it the natural choice for one-offs and print-on-demand.

Wash life. Good, and it fails gracefully: DTG fades gradually instead of cracking, so contrast is the thing you watch. Properly cured, it outlasts transfers comfortably.

Screen print

How it works. Ink pushed through a stencilled mesh screen, one colour at a time. A QR code is one colour — the ideal screen-printing job.

Scan reliability. The best of the three at real sizes: a thick ink deposit gives the highest contrast and the sharpest module edges. The one caution is the mesh — a coarse screen and a tiny code do not mix, so keep modules comfortably sized, which you should anyway.

Cost and DIY. Setup — screen, emulsion, exposure — makes a single shirt expensive and a run of twelve or more the cheapest per shirt here. It is the hardest method at home, though a one-colour code is the friendliest first screen print there is.

Wash life. The durability benchmark. A good screen print is still scanning at wash fifty and beyond; it is the method the 50-wash standard was written around.

The verdict

• One shirt, tonight, no gear: iron-on transfer — and scan-test it after a few washes.
• One shirt, best feel, somebody else prints it: DTG.
• A run of shirts that must survive years of laundry: screen print.
• Vinyl at home: heat-transfer vinyl, with the code printed big enough to weed.

Every method fails the same way — too small, too faint, too crowded — and every one of those failures is visible before the shirt is worn. The method is your choice; the standard is not negotiable. And once the code is on the shirt, a Scanworn page is what it points at — change what it shows whenever you like.