How Amiibo Use NFC — and the NTAG215 Chip Behind Them

What Chip Is Actually Inside an Amiibo

Every amiibo figure and card runs on an NXP NTAG215 — an NFC Forum Type 2 Tag compliant chip, the same family used in ordinary NFC stickers and cards. Nintendo picked it because it's passive. No battery, no charging, and cheap enough to embed in a plastic figure or a paper card without changing the price much.

Here's what's ahead: how much memory that chip gives a game to work with, how a console reads and writes it, and where else you'll run into the exact same chip.

How Much Memory an Amiibo Actually Has

504 bytes of user memory, out of 540 total

The NTAG213/215/216 family is really one chip design sold in three memory sizes: NTAG213 gives you 144 bytes of user memory, NTAG215 gives you 504, and NTAG216 gives you 888. Amiibo uses the middle size. All three share the same 13.56 MHz frequency and ISO/IEC 14443-A air interface, organized as EEPROM across 135 four-byte pages — 540 bytes total on the 215.

What eats into that 504 bytes

Of that 504 bytes, only about 428 are writable game-save data — split into a 36-byte block and a 392-byte block. The rest of the chip (UID, lock bytes, capability container, configuration and password pages) is fixed or write-protected. With that little room to work with, amiibo compatibility stays tight; a title can't store much more than one save slot on a single figure.

How a Console Reads an Amiibo

Detection through the Type 2 Tag / NDEF model

NTAG215 belongs to the NFC Forum's Type 2 Tag class, which defines exactly how a reader in reader/writer mode finds and reads an NDEF message on page-organized memory. A console identifies a tag as an amiibo first by its ATQA and SAK values — the low-level NFC identifiers every Type 2 Tag reports before any user data is touched.

A password derived from the tag's own UID

Here's the part that surprises people: there's no single shared password that unlocks every amiibo. Each figure's write password is algorithmically derived from that specific tag's own unique ID, so the console computes the password on the fly from the UID it just read, instead of storing one master key for the whole product line. The tag just holds encrypted bytes. Decrypting and interpreting the save data happens on the console, not the chip.

That's also why most amiibo hold one compatible game's data at a time — a Mario figure carrying Super Smash Bros. data needs that data cleared before it can store Mario Party progress instead. The Wii U reads amiibo through its GamePad, Switch reads through the Joy-Con (R) or Pro Controller, and the New 3DS/2DS XL and Switch 2 have NFC built in. Original 3DS/2DS models needed a separate reader accessory.

Where Else You'll Run Into NTAG Chips

NTAG213/215/216 isn't amiibo-exclusive. You'll find the exact same family in NFC stickers, digital business cards, Wi-Fi-share tags, and smart-home automation triggers. Tapped a sticker to join a Wi-Fi network or trigger an iOS Shortcut lately? There's a decent chance it was running on this same chip.

Nintendo picked this line for its low cost and simple page-based memory, not for security. NXP also makes chips built for tap-to-verify authentication instead of passive storage — a different job than what an amiibo needs to do.

Checking Your Own Amiibo Collection with NFCore

To see this for yourself, open NFCore and tap an amiibo you own to its tag inspector. You'll see its UID, its tag type (NTAG215), and a raw memory dump — handy for confirming a secondhand figure is a genuine NTAG215 rather than a cheap low-memory clone before you pay for it. This is standard tag inspection, same as reading any other NFC card or sticker you own — NFCore's tools are scoped to tags you own or control. Grab NFCore on the App Store or Google Play to try it on your own collection.

Frequently Asked Questions

What NFC chip is inside an amiibo?

Every amiibo figure and card uses an NXP NTAG215 — an NFC Forum Type 2 Tag compliant chip with 504 bytes of user memory. It's the same chip family used in NFC stickers and cards, just with more memory than the smaller NTAG213.

Can I read my own amiibo with NFCore?

Yes. NFCore's tag inspector shows an amiibo's UID, tag type (NTAG215), and raw memory dump — useful for confirming a figure is genuine or troubleshooting a read that isn't registering.

Why can an amiibo only hold one game's data at a time?

The 504 bytes of user memory on an NTAG215 aren't large enough to hold save data for multiple titles side by side, so most games that write to an amiibo require clearing the existing save before storing new data.

Is reading my own amiibo the same as cloning someone else's?

No — inspecting a tag you own is standard NFC tag management, no different from reading any other NFC card or sticker you own. NFCore's cloning tools are scoped to tags you own or control.

Conclusion

There's no secret sauce behind an amiibo. It's an off-the-shelf NXP NTAG215, the same chip you'll find in ordinary NFC stickers and business cards, running a UID-derived password scheme and a well-documented page-based memory model. Once you know how to read that model, the same chip literacy carries over to any NFC tag you own — not just the ones shaped like video game characters.