Short answer
A vCard QR code stores your contact details in the vCard 3.0 text format inside the pattern. Phone cameras recognise it and offer to create a new contact. Keep it to name, phone, email and website so the code stays small enough to print on a business card.
What goes in, and what to leave out
The generator writes a vCard 3.0 record: BEGIN:VCARD, a version line, your name in the structured N field and display FN field, then only the fields you filled. Phones read the name, organisation, title, phone numbers, email, website, address and a note.
The more you add, the denser the code. In our own tests, a short card (name, mobile, email) comes out at version 8, 49 modules a side, at error correction M. Add a company and website and it reaches version 11 (61 modules); a full street address, job title and note push it to version 14. At 2.5 cm wide, 49 modules gives about half a millimetre per module, which is fine from a print shop. At 61 modules you either print the code 3 cm wide or drop to error correction L, which brings the same card down to 53 modules. The info line under the preview shows the version and module count as you type.
Business card tips
- Back of the card, plain background. Give the code its own space, with a white margin at least four modules wide. A pattern or photo behind it will cost you scans.
- Size: 2 cm is the floor, 2.5 cm is kinder. People hold a card close, but older phones focus poorly below about 10 cm.
- Print your details as text too. The code is a shortcut, not a replacement. Some people will just want to read your number.
- Use SVG for the printer. It stays sharp at any size. Ask the printer not to "optimise" or rasterise it at low resolution.
- Proof it. Scan a printed proof with two phones and check that the contact saves with the right name order and number format.
The print templates page has a business card layout with the code placed at a safe size, and the print guide covers contrast and quiet zones in more depth.
Sources
Questions
Why is my vCard QR code so dense?
Every field adds characters, and an address or note can double the size. A dense code needs to be printed larger to scan reliably. On a business card, keep to name, company, phone, email and website, or use a link to a square page with everything else.
Will it work on iPhone and Android?
Yes, vCard is the standard contact format both platforms import. Current camera apps show the contact and an option to add it.
Can I update the details later?
No. The details are inside the printed code. If you change jobs or numbers often, point a URL code at a page you control and keep the vCard for cards with a short print run.
Which vCard version does this use?
vCard 3.0, defined in RFC 2426. It is the version phones import most consistently. Commas, semicolons, backslashes and line breaks in your text are escaped as that standard requires.