RFID Ear Tags for Sheep and Goats: Types, Standards, Buying Tips
Buying guide to RFID ear tags for sheep and goats: ISO 11784/11785 at 134.2 kHz, FDX-B vs HDX, heat and UV resistance, and visual vs electronic tags.
RFID ear tags for sheep and goats should follow the international ISO 11784/11785 standard and work at 134.2 kHz. They come in two technologies: FDX-B, the most common, which transmits continuously while the reader powers it, and HDX. Choose tags that match your reader, resist heat and UV light, and carry a printed number identical to the one stored in the chip.
If you are still asking "is electronic tagging worth it for my herd?", start with our article RFID ear tags for sheep: is it worth it?. This article is the next step: you have decided to go electronic and now want to know exactly what to buy and how to make sure the tags will work with your reader and app.
The international standard: ISO 11784 and ISO 11785
The two standards work together:
- ISO 11784 defines the structure of the number stored in the chip, a unique code usually shown as 15 digits, often starting with a country or manufacturer code.
- ISO 11785 defines how the chip and reader communicate, at the low frequency of 134.2 kHz.
Why does this matter? A tag that meets the standard can be read by any reader that meets it, so you are not locked into one supplier. A non-standard tag may be cheaper but may only be readable with that company's device.
FDX-B or HDX?
| Item | FDX-B | HDX |
|---|---|---|
| How it works | The chip transmits continuously while the reader powers it | The chip alternates between charging from the reader and transmitting |
| Read speed | Usually fast reads | Depends on reader and use |
| Use in sheep and goats | The most common | Less common in small flocks |
| What to check | Reader supports FDX-B | Reader supports HDX |
The golden rule: tag and reader must speak the same language. Many modern readers read both, but do not assume it; ask the supplier and test before buying in bulk.
Types of electronic ear tags
- Button tag (two-piece, male and female). Small and light, with the chip in the button. Very common in sheep and goats.
- Electronic flag tag. A large panel with a clearly printed visual number and a chip in the tag. Visual and electronic reading in one piece.
- Matched pair. An electronic tag in one ear and a visual tag with the same number in the other. Practical if you want to keep an internal colour system.
- Rumen bolus. A capsule swallowed into the rumen. It does not fall out like an ear tag, but needs skilled application and is less used on small farms.
Visual or electronic tags?
| Item | Visual tag | RFID electronic tag |
|---|---|---|
| Reading | By eye, affected by dirt, angle and distance | By reader in a second, no need to read digits |
| Errors | Misreading and miswriting happen | The number goes to the app exactly as stored |
| Cost | Lower per head | Higher per head, plus a reader |
| Best use | Small herds the owner knows by sight | Larger herds, frequent weigh and vaccination days, documented sales |
| Works without a device | Yes | Needs a reader, so a visual number is still useful |
Our practical recommendation is electronic plus visual with the same number. To design your visual numbering and colours, see livestock numbering and ear tag colours.
Heat and UV in hot climates
Strong sun and high summer temperatures, as in the Gulf, wear plastic out: a poor tag cracks or turns brittle, and its colour and printed number fade. When buying:
- Ask about the material and its resistance to UV and heat, and request whatever test data the supplier has.
- Prefer laser-printed visual numbers over surface printing that fades.
- Choose a size suited to age: a heavy tag on a newborn's ear increases tearing and losses.
- Tag in the cool part of the day and disinfect the applicator between animals to limit infection in fly season. See also heat stress in livestock.
Checklist before you buy
- Tags meet ISO 11784/11785 at 134.2 kHz.
- The chip technology (FDX-B or HDX) is supported by your reader.
- The printed number matches the number stored in the chip.
- The material resists heat and UV.
- The size suits your animals' ages, and the applicator fits the tag.
- If you need tagging for an official purpose, check the authority's requirements; in Saudi Arabia, see the livestock tagging request on Naama.
- You tested a sample with your reader and app before ordering the full quantity.
How many tags to order, and how to start
Do not order for today's headcount only. Count three things:
- The current herd you will tag now, or the group you will start with (the breeding ewes, for example).
- Expected births in the coming months, so newborns are not left untagged for lack of stock.
- A reserve for losses. Some tags fall out or get damaged over time; keep spares and record every replacement against the same animal.
The safest way to start: tag one group, run a full cycle (weighing, vaccination, stock count) with the reader and the app, and extend to the rest of the herd once you are sure everything works as expected.
Reading tags with a Bluetooth reader in Throf
An electronic tag with no record behind it is just a number. In Throf you pair a Bluetooth (BLE) RFID reader with the app on Android and iOS (iOS needs a BLE-capable reader). When you add or look up an animal, the tag number is filled automatically and the animal's file opens: breed, mother, father, vaccinations, weights and cost. With a smart scale that reads the tag, the weight is saved in the animal's history without typing; see our livestock scale buying guide.
Request a quote
Throf provides RFID ear tags, Bluetooth readers and smart scales. Send us your species, herd size and age groups: request a quote for tags or a scale on WhatsApp. Register your herd on the free plan, or subscribe and pay online for larger herds (coupon THROF15 for 15% off).
FAQ
What is the standard for livestock RFID ear tags?
The international standard is ISO 11784 for the number structure and ISO 11785 for communication, at 134.2 kHz. A compliant tag can be read by any compliant reader that supports the same technology.
What is the difference between FDX-B and HDX?
An FDX-B chip transmits continuously while the reader powers it and is the most common in sheep and goats. An HDX chip alternates between charging and transmitting. What matters is that your reader supports your tags' technology.
Do electronic ear tags survive hot summers?
It depends on material and quality. Choose UV- and heat-resistant tags with laser-printed numbers and ask the supplier for test data.
Do I still need a visual tag with an RFID tag?
It is recommended. A matching visual number lets you identify the animal by eye if the reader fails or its battery runs out.
General guidance only — it does not replace your veterinarian or the competent authority in your country.
