Card, sticker or keyfob for a business card?
A card, because a business card is given away and the others are objects you keep. That difference decides the economics, the etiquette and the antenna size, and it is why the alternatives suit a different job rather than the same job cheaply.
Given away or kept
A business card leaves your hands and does not come back. That single fact governs everything.
It means unit cost matters, because you will hand out many. It means the object must survive a wallet rather than a wall. And it means the recipient decides what happens to it afterwards.
A sticker or a keyfob is something you keep and present repeatedly. That is a different job with different economics: fewer units, longer life, and you control where it lives.
Confusing the two produces the common mistake of buying one expensive object and presenting it to everyone, which works and is not a business card.
Why the card format wins
The antenna is as large as a pocketable object allows, so it reads more forgivingly than anything smaller. For a stranger's first attempt, that margin matters.
It is the shape people expect, so it needs no explanation and files where cards file.
It prints well, which lets the same object carry your name legibly and a printed address for anyone who cannot tap.
And it is cheap enough per unit to hand out without counting, which is what a business card has to be.
What the others are for
A keeper card, presented from your own wallet at every meeting and never given away, is a legitimate and different tool. One good object, no unit economics, and you can spend more on it.
A sticker on the back of your phone turns your own device into the thing you present. It works, and it looks like an accessory rather than a card.
A keyfob or a token is for objects and access rather than introductions. The antenna is small and the format says nothing about who you are.
None of these is wrong. They answer the question of how you present yourself, not the question of what you leave behind.
Materials, briefly
Plastic card stock is the default: it prints, it survives a wallet, and it costs least.
Metal and wood are chosen for the impression they make, and both come with constraints that are worth understanding before ordering. A metal card reads from one face only and needs a construction built around that.
Whatever the material, the antenna is the same size and the chip requirement is the same. The material buys an impression rather than a capability.
And if you are handing out many, order a small quantity first and carry them for a fortnight. A card that looks right on a screen and feels wrong in a wallet is worth discovering before the full run.
Frequently asked questions
Can I use one card for everyone?
Yes, and that is a keeper card rather than a business card. It is a valid approach with different economics, since you never give it away.
Is a metal card worth it?
For the impression, sometimes. It reads from one face only and costs more, so decide whether the impression justifies both.
What about a sticker on my phone?
It works and presents your own device rather than an object you leave. Useful alongside cards rather than instead of them.
Does the format change what the card can hold?
No. Memory and features belong to the chip, and the format decides the antenna size and therefore how forgiving the tap is.