Glossary

NTAG

A family of NFC chips, NTAG213 to NTAG216, found in most cards and stickers. They differ in memory size, from roughly 144 to 888 bytes. Since a card only stores a web address, the smallest is enough.

NTAG is NXP's line of NFC Forum Type 2 chips, and it is what sits inside most of the blank cards, keyrings and stickers sold online. Three references cover almost everything on the market:

ChipUser memoryTypical use
NTAG213144 bytesA web address, which is all a card needs
NTAG215504 bytesLarger payloads, known for game figurines
NTAG216888 bytesRarely justified on a card

A LeadShake address of forty characters occupies well under a hundred bytes once wrapped in an NDEF record. NTAG213 therefore has room to spare, and paying for NTAG216 buys memory a business card will never use.

The lock bit is one way

Every NTAG carries a lock bit. Setting it makes the tag read only, permanently, and no application will undo it. Writing apps offer it as a checkbox, sometimes next to the write button, which is where accidents happen.

Leave a tag unlocked unless you have a reason not to. A card that can be rewritten is a card you can point at a new campaign next season instead of throwing away.

Compatibility

Anything advertised as NFC Forum Type 2 behaves the same way for this purpose, whether the chip is an NTAG or a competing part. No card sold by any vendor is technically required: a blank tag bought anywhere holds the same address and opens the same page. See NFC for how the read itself works.

Questions

NTAG213. Its 144 bytes of user memory hold a web address several times over, and a card stores nothing else. The larger references exist for payloads a card does not carry.

Related terms

NFC
Near Field Communication, a radio standard that lets two devices exchange a small amount of data when they are a few centimetres apart. On a business card it holds one thing: a web address. The card carries no battery and stores no personal data.
Campaign
In LeadShake, one card and the register that goes with it. Your account has a default campaign that never expires, and each Event Pass opens an extra one for 30 days so an event keeps its contacts separate.

Go further