How NFC business cards work (without the engineering degree)

Your card has a tiny NFC chip and an antenna loop inside the plastic. The chip holds a web address. Your phone has an NFC reader. Hold them close. The phone reads the address and opens it in the browser.

That is the whole trick. Everything else is details and edge cases.

NDEF (NFC Data Exchange Format) is the standard way consumer tags store small payloads. For business cards, the payload is almost always a URL record.

Think of NDEF as an envelope. Inside the envelope is a note that says "open https://halve.cc/p/yourname" or similar.

You do not need to encode vCard data on the chip itself for modern workflows. A URL to a live profile is simpler to update and richer (photos, buttons, analytics). The profile page handles contact save.

HALVE programs NTAG213 chips with a redirect URL to your profile before shipping. You link the card during activation. Later profile edits happen on the web, not by rewriting the chip.

iPhone (XR and later for background tag reading): OS detects tag, shows notification or opens link directly depending on iOS version and state. Hold tag near top edge.

Android: NFC service reads tag, opens default browser. Sweet spot often center back. Some manufacturers move it slightly.

No HALVE app required for the recipient. They need a browser and network. WiFi or mobile data.

If nothing happens: NFC off in settings, thick phone case, metal plate between tag and phone, or tag damaged.

DIY: blank tag + NFC Tools app + your URL. Cheap per unit, error-prone at scale.

Pre-programmed: manufacturer writes URL in factory or before ship. You associate card with account.

I prefer pre-programmed for client-facing cards because a wrong encode is invisible until someone taps at a bad time.

When people say "programmed before shipping" they mean the chip already contains the opening URL or a HALVE activation URL that routes to your profile once you claim the card.

HALVE uses NTAG213 chips. Each tag holds a redirect URL, not your full profile. Read distance is centimeters, intentional for privacy. You tap deliberately, not across a room.

NFC is not Bluetooth. No pairing. No battery in the card. Passive tag powered by phone's field.

Metal-heavy card designs can shrink read range if metal covers the antenna area. PVC is forgiving.

Your tag should open a domain you trust. Random street tags are risky to tap. Your own card in a conversation is low risk.

Use HTTPS profiles. Do not encode executable shortcuts unless you know what you are doing.

QR backup on profile helps when NFC fails. NFC vs QR.

You can print QR on plastic instead of NFC. Scanning requires camera, framing, light. Tapping is one motion when it works.

Best setup: NFC inside card, QR on profile page as fallback. Same destination URL.

Contact save flow explained: tap to share without app.

Free profile to see the destination page. Order PVC card pre-programmed. More questions: FAQ. About HALVE: about page.