QR Keychain Template
A pocket-sized tag with one hole for a ring and a raised QR code on the front. It is the smallest of the three templates, which makes the choice of link more important than anything else.
Small tag, small modules
On a keychain the code has very little room, so the tool uses the small module setting, 1.7 mm per module. The generator's safe minimum is 1.5 mm, which leaves little headroom: a link that needs many modules cannot be squeezed any further without the code becoming unreliable. The practical answer is a short link, ideally one that fits in about 25 modules.
If your address is long, shorten it with a redirect you control. You get a smaller tag, and you can point the redirect somewhere else later without reprinting.
Approximate measurements
All figures use the small setting (1.7 mm modules). A flat tag is 4.2 mm thick: 3.0 mm base plus 1.2 mm of relief.
| Code size | QR width | Keychain (width × height) |
|---|---|---|
| 25 modules (short link) | 42.5 mm | 50.5 × 59.5 mm |
| 25 modules with raised text | 42.5 mm | 50.5 × about 66 mm |
| 29 modules (longer link) | about 49.3 mm | 57.3 × 66.3 mm |
| Ring hole | 1 hole, 4.2 mm diameter, at the top | |
With a 42.5 mm code, the "ten times the width" rule of thumb gives a scanning distance of around 40 cm, which is plenty for holding a keychain up to a phone.
Who it is for
- Makers and market sellers who hand out a tag linking to their shop or portfolio.
- Bags, luggage and gear, with a link to a contact form rather than your personal details.
- Clubs, classes and events, where each member gets a tag pointing to the schedule or group page.
- Small businesses that want a giveaway people will keep on their keys instead of a card that gets lost.
Tips for using it
- Keep the link short. Every extra four modules makes the tag noticeably bigger.
- Do not encode a home address or phone number in a tag that could be lost; link to a contact page you can edit.
- Check that your ring or cord fits through the 4.2 mm hole before you print a batch.
- A logo in the middle forces a higher error correction level, which grows the code. Test a logo version before committing to it.
- Use two contrasting colors for the base and the modules, as described in the 3MF versus STL guide.
- Read QR keychains and wall plaques for more on holes and mounting.
Frequently asked questions
Why does the keychain template recommend short links?
The tag is small, so the modules are small too. A short link keeps the code at about 25 modules, which fits a tag of roughly 50 by 60 mm. A longer link adds modules and either enlarges the tag or pushes the modules below the safe size.
Will my key ring fit through the hole?
The hole is 4.2 mm across, which suits a thin split ring, a small carabiner clip or a cord. A chunky ring may not pass through, so check yours before printing.
How much does raised text add?
Optional raised text lengthens a 25-module keychain from about 59.5 mm to about 66 mm. Skip it when you want the smallest possible tag.
Will the code wear out in a pocket?
Raised modules can rub smooth against keys and fabric over time. Treat the keychain as a cheap item that you reprint when it gets worn, and link to an address you control so a new one still works.
Start from this template
Open the tool with the Keychain format selected, paste a short link and download a file for a test tag.
Use this template