Pet microchipping is built on two international standards—ISO 11784 and ISO 11785.
These standards define how a pet’s RFID microchip stores data and how scanners read it, ensuring global compatibility for pet identification.
If you're selecting or supplying pet ID microchips, understanding these standards is essential.

This guide explains what ISO 11784 and ISO 11785 microchips are, how they work, and why the 134.2 kHz FDX-B microchip has become the worldwide standard for pets.

1. What Is an ISO 11784 / ISO 11785 Microchip?

ISO 11784 Microchip (ID Structure Standard)

ISO 11784 defines the format of the identification code stored inside the RFID microchip.
A standard ISO11784 microchip contains a 15-digit numeric ID, including:

• Country / manufacturer code (3 digits, ICAR-approved)

• Unique identification number (12 digits)

This ensures each chip number is globally unique and traceable.

ISO 11785 Microchip (Technical Reading Standard)

ISO 11785 defines how RFID readers communicate with the chip, including:

• Frequency (134.2 kHz)

• Modulation method

• Coding protocol

• Activation/response behavior

ISO 11785 determines whether a reader can detect and decode the chip.

 ISO 11784 = what data looks like
ISO 11785 = how the chip is read

2. Why 134.2 kHz FDX-B Became the Global Standard

ISO animal microchips operate at 134.2 kHz, using FDX-B (Full Duplex B) modulation.
This frequency offers:

• Long read distance in animal tissue

• Stable communication

• Low energy requirement

• Excellent anti-interference performance

• Full compatibility with universal scanners

Today, FDX-B 134.2 kHz is the mandatory standard for pets worldwide, accepted by:

• Veterinary clinics

• Animal shelters

• Border control

• International pet travel agencies

• WVO / ICAR animal identification systems

If a chip is not FDX-B, it cannot be recognized internationally.

3. Differences Between ISO11784 and ISO11785

4. Technical Structure of an ISO 11784/11785 Microchip

An ISO-standard pet microchip usually contains:

4.1 IC Chip (FDX-B compliant processor)

Stores the 15-digit code and handles communication.

4.2 Copper Coil Antenna

Receives energy from the scanner and sends the chip’s ID back.

4.3 Bioglass Capsule (Schott glass)

Protects internal components and is safe for long-term implantation.

4.4 Anti-migration Coating (Paralyne-C)

Prevents the microchip from moving under the skin.

4.5 Sterile Syringe or Injector

Used for safe implantation—must follow ISO sterile packaging standards.

5. FDX-B vs HDX vs Non-ISO Chips

FDX-B (ISO Standard) – Recommended for Pets

• Frequency: 134.2 kHz

• Standard ID format

• Read by all universal scanners

• Required for international travel

HDX (Used in Livestock Monitoring)

• Not commonly used for pets

• Slower response time but longer read range

• Requires special scanners

Non-ISO Chips (125 kHz: EM4100/TK4100)

• Cheaper

• Limited compatibility

• Not readable by international pet scanners

• Not suitable for animal ID in most countries

 For pets: Always choose ISO11784/11785 FDX-B microchips.

6. ICAR Approval – Why It Matters

ISO is the technical standard, but ICAR (International Committee for Animal Recording) controls manufacturer code allocation.

An ICAR-approved microchip means:

• Globally recognized manufacturer code

• Compliance with ISO tests

• Better data accuracy

• Guaranteed ID uniqueness

Professional buyers and government tenders often require ICAR-certified suppliers.

7. How ISO Microchips Are Read (Reader Interaction)

1. Scanner sends a 134.2 kHz signal

2. Microchip coil receives energy

3. IC chip activates

4. Chip transmits its 15-digit ID using FDX-B modulation

5. Reader decodes and displays the ID

6. ID matches pet database → owner information is located

Because all ISO readers follow ISO11785 protocols, global interoperability is possible.

8. Applications of ISO 11784/11785 Microchips

✔ Pets (Dogs, Cats, Rabbits, Small Animals)

Government-mandated identification, pet travel, owner management.

✔ Livestock Identification

Cattle, pigs, sheep—though HDX chips are also common.

✔ Wildlife & Zoo Animals

Birds, reptiles, conservation projects.

✔ Veterinary Hospitals & Shelters

Fast identification & medical record matching.

✔ Pet Travel and Quarantine Agencies

ISO FDX-B chips required for entry into many countries.

9. How to Verify a True ISO11784/11785 Chip

Buyers should check:
✔ 134.2 kHz frequency
✔ FDX-B communication protocol
✔ 15-digit ISO ID
✔ ICAR manufacturer code
✔ ISO test certificate
✔ EO-sterilized packaging
✔ Anti-migration coating
✔ Universal scanner compatibility

If any of the above is missing → it may not be a true ISO/ICAR chip.

Conclusion

ISO 11784 and ISO 11785 define the global standard for pet RFID microchips.
They ensure every microchip has a unique ID, uses FDX-B technology, and is readable by scanners worldwide.

For pet identification, travel, veterinary use, or large-scale animal management, 134.2 kHz ISO11784/11785 FDX-B microchips are the safest and most internationally recognized solution.