NFC Standards Reference
NFC is not a single specification but a layered stack of ISO, IEC, ECMA, and NFC ForumNFC ForumIndustry body developing NFC standards, specifications, and certifications since 2004View full → documents. Understanding which standard governs which aspect of the system prevents costly integration mistakes and ensures that hardware, firmware, and software components interoperate across vendors and geographies.
Use the Compatibility Checker to verify that a specific chip, reader, and host combination satisfies the standards profiles required by your deployment.
ISO 14443: Proximity Cards
iso-14443 is the foundational standard for contactless smart cards operating at 13.56 MHz up to 10 cm. It consists of four parts:
| Part | Title | Key Content |
|---|---|---|
| 14443-1 | Physical characteristics | Mechanical dimensions, bending tests |
| 14443-2 | RF power and signal interface | Field strength (1.5–7.5 A/m), ASK modulationASK modulationSignal amplitude variation encodingencodingData writing to NFC tags during manufacturing productionView full → data on 13.56 MHz carrierView full →, ask-modulation schemes |
| 14443-3 | Initialization and anti-collisionanti-collisionProtocol for selecting individual tags from multiple in RF fieldView full → | anti-collision loops, UID structure, ATQA, SAK bytes |
| 14443-4 | Transmission protocol | T=CL block protocol, RATS, ATS, chaining |
Two Type A/B variants coexist. nfc-a (Type A) uses modified-miller encoding for the reader-to-card direction and manchester-coding for card-to-reader load-modulation. nfc-b (Type B) uses NRZ-L encoding in both directions with BPSK subcarrier modulation.
Most consumer NFC tags — NTAG, MIFARE Ultralight, DESFire — are ISO 14443ISO 14443Standard for contactless smart cards at 13.56 MHz (Types A and B)View full →-3A (NFC-A) devices. ISO 14443-4 adds the full transport layer used by DESFire and payment cards, enabling secure channel protocols.
ISO 15693: Vicinity Cards
iso-15693 targets longer read ranges (up to 1 m) for supply-chain and asset-tracking scenarios. The standard uses 10% or 100% ASK modulation and either 1-of-4 or 1-of-256 pulse-position modulation (PPM).
| Parameter | ISO 14443 | ISO 15693ISO 15693Standard for vicinity-range smart cards, 1+ meter read rangeView full → |
|---|---|---|
| Read rangeRead rangeMaximum communication distance between reader and tagView full → | ≤ 10 cm | ≤ 100 cm |
| Data rate | 106–848 kbit/s | 6.6–26.5 kbit/s |
| Addressing | 4–10 byte UID | 8-byte UID |
| Memory access | Block/page | Block (typically 4 bytes) |
| Anti-collision | Bit-frame, NVB | Time-slot (16 slots) |
| NFC Forum mapping | Types 1–4 | Type 5 (nfc-v) |
ISO 15693 tags — NXP ICODE SLI, TI Tag-It HF — are called "vicinity" cards and require readers with larger antennas. They appear as NFC Forum Type 5 (nfc-v) in Android and iOS.
NFC Forum Specifications
The nfc-forum publishes specifications that sit above ISO 14443/15693, defining the NDEF format, tag type platform interactions, and operating modes. Key documents:
| Specification | Version | Coverage |
|---|---|---|
| NDEF Technical Specification | 1.0 | Message, record, TLV format |
| Tag Type 2 Platform (T2T) | 1.0 | NTAG, Ultralight — memory map, commands |
| Tag Type 4 Platform (T4T) | 1.1 | DESFire, JCOP — ISO 7816 APDU |
| Tag Type 5 Platform (T5T) | 1.0 | ICODE — ISO 15693 mapping |
| nfcip-1 (ECMA-340 / ISO 18092) | 3rd Ed. | Peer-to-peer RF layer, llcp foundation |
| nfcip-2 (ECMA-352 / ISO 21481) | 2nd Ed. | Selects between 14443, 15693, and 18092 |
| Digital Protocol Specification | 2.3 | Unified analog/digital layer for NFC-A/B/F/V |
| Activity Specification | 2.2 | Polling loop, technology detection sequence |
| llcp (Logical Link Control Protocol) | 1.3 | P2P connection-oriented and connectionless transport |
| SNEP (snep) | 1.0 | Simple NDEF Exchange Protocol over LLCP |
ECMA Standards
ECMA International adopted nfcip-1 as ECMA-340 and nfcip-2 as ECMA-352, which were subsequently adopted as ISO 18092 and ISO 21481. ECMA-356 covers RF interface test methods. These ECMA versions are freely downloadable from ecma-international.org and are functionally identical to the ISO versions.
nfcip-1 defines the physical layer (13.56 MHz, ASK, Manchester/Miller) and the link layer for active and passive communication modes. It is the foundation for Android Beam (now deprecated) and NFC peer-to-peer file transfer.
NFC Forum Certification
nfc-forum-certification validates that a device correctly implements the NFC Forum specifications, covering analog performance, digital protocol behavior, and NDEF handling. The certification program includes:
| Test Suite | Scope |
|---|---|
| Analog | Field strength, waveform shape, modulation depth |
| Digital | Command timing, anti-collision sequences, error recovery |
| LLCP | Connection establishment, service discovery, data transfer |
| SNEP | NDEF push correctness |
| Device Under Test (DUT) | End-to-end tag read/write on a certified poller |
Certification is mandatory for devices carrying the N-MarkN-MarkOfficial NFC Forum certification mark for compliant productsView full → logo. Chip vendors typically pre-certify their silicon; OEMs integrating that silicon into a new form factorform factorPhysical shape/packaging of NFC tags: stickers, cards, wristbandsView full → must certify the complete product.
For application-layer interoperabilityinteroperabilityCross-manufacturer device/tag compatibility guaranteeView full → details across platforms, see NFC Application Development Guide and NDEF Specification Deep Dive.