Buying guide
NFC stickers, and which one you actually need
Most pages selling NFC stickers list the chip, the memory and the read range, which tells you nothing about whether it is the right sticker. The useful question is what happens when someone else taps it, or tries to fake it.
The only decision that matters
Every NFC sticker holds a link. The difference between a four-cent sticker and a cryptographic one is whether anybody can change that link, and whether a copy can be told apart from the original.
That gives you two honest categories, and most buyers need the cheap one.
A plain sticker is right when the finder is on your side
Lost luggage, a water bottle at school, a bike, a laptop left in a taxi. Whoever taps it is trying to return your thing. Nobody has a motive to fake the tag, so paying for cryptography is paying for nothing. We use ICODE SLIX2 for this.
A cryptographic sticker is right when someone has a reason to lie
Proving an item is genuine, proving who currently holds it, proving an inspection actually happened at the object. Here the tag is the evidence, so a copy has to fail. That needs NTAG 424 DNA, which signs every tap with a key that never leaves the chip.
The trap with blank stickers
A pack of blank NFC stickers off a marketplace arrives unlocked. That is not a defect, it is the point: you are meant to write your own link. But it also means anyone who picks up your item can hold their phone to it and replace your link with theirs, in about four seconds, with a free app.
If the sticker is there to recover a lost item, that is survivable. If it is there to prove something, it defeats the whole purpose. Check whether the seller locks the tag and who holds the key, because "secure" on a product listing usually means neither.
What no NFC sticker can do
Worth saying plainly, because the category oversells itself constantly.
- It is not a tracker. There is no battery and no radio of its own. It knows nothing until someone taps it. If you want to know where something is right now, you want GPS or a Bluetooth tracker.
- It cannot be read from across the room. A few centimetres is the whole range. For warehouse-scale reading you want UHF RFID.
- It is not uncopyable. The bytes on any tag can be written to another chip. What a cryptographic tag gives you is that the copy fails verification, which is a different and more defensible claim.
What we sell
Three packs, all 25 tags with a year of NFCFind service. We are telling you which to buy, including when the cheapest one is the right answer.
| Pack | Tags | Buy it when |
|---|---|---|
| Everyday $19.99 | 25 ICODE SLIX2 | Bags, bottles, keys, luggage, kids’ kit. Recovery, not proof. |
| Ultra Secure $29.99 | 25 NTAG 424 DNA | Laptops, cameras, tools, documents. Where a copy must fail. |
| Dual Tech $24.99 | 15 SLIX2 + 10 424 DNA | A household with both kinds of item. The usual answer. |
Not buyable right now
The packs sell through Amazon and that listing is currently unavailable while a seller-account problem is resolved. We would rather say so here than send you to a dead page. The app and the service work regardless, and everything above is still the advice we would give you.
Questions people actually ask
- What is an NFC sticker?
- A thin adhesive label with a chip and a small antenna printed inside it. There is no battery. A phone held within a few centimetres powers the chip for long enough to read it, which is why the sticker can be flat, cheap and last for years.
- Do NFC stickers work with iPhone and Android?
- Yes. Every iPhone from the XS onward reads NFC tags in the background with no app, and Android has done so for far longer. Whoever taps your sticker does not need to install anything.
- How much data fits on an NFC sticker?
- Less than people expect, and it rarely matters. A typical tag holds a few hundred bytes, which is enough for a URL. The usual pattern is to store a short link and keep the real content on the web, so it can change without touching the sticker.
- Can an NFC sticker be erased or overwritten?
- An unlocked one, yes, by anyone with a phone and a free writer app, in seconds. That is the single biggest thing people miss when buying blank tags. A locked tag cannot be rewritten, which is why it matters whether the seller locks them and who holds the key.
- Are NFC stickers waterproof?
- The chip and antenna tolerate moisture well; the adhesive and the label face are what fail. For a bottle, a bike or anything that lives outdoors, put the sticker somewhere it will not be scrubbed, or cover it.
- Will an NFC sticker work on metal?
- Not reliably on bare metal, which detunes the antenna. You need a tag with a ferrite layer, sold as on-metal or anti-metal. A standard sticker on a laptop lid or a toolbox will read poorly or not at all.
- What is the difference between NFC and QR?
- A QR code is an image, so it can be photographed and reproduced perfectly, and it can be scanned from a screen across the room. An NFC sticker has to be physically touched, and a cryptographic one signs each tap so a copy fails the check. For a menu, use QR. For proving someone was at the object, use NFC.
If you need the secure kind
The detail on how the cryptography works, what it stops and what it does not, is on its own page.
NTAG 424 DNA, and what it actually secures