RFID tags: what is inside them, what they do, what they cost.
A chip, an antenna, a piece of film — and a number that can be read from several metres away. This page explains the construction, the frequencies, the form factors and the prices of RFID tags, without marketing language and with the limits that come with them.
What an RFID tag is and what it is made of
An RFID tag is a data carrier that transmits a stored number by radio to a reader as soon as it enters that reader's field. It has three parts: a microchip roughly half a millimetre to a millimetre across, an etched or printed antenna, and a carrier material. Passive tags have no battery — they draw all of their energy from the radio field of the reader.
The chip
The chip is an integrated circuit with a small amount of non-volatile memory. It carries no computing logic in the sense of a processor, but a state machine: it wakes up when enough energy arrives, listens for commands from the reader and answers with the contents of its memory. Typical chip areas are under a square millimetre.
The antenna
The antenna takes up most of the area. At UHF it is usually a dipole of aluminium or copper, around 70 to 100 millimetres long. Its length follows directly from the frequency: the lower the frequency, the larger the antenna. That is why HF tags are usually coils with several windings while UHF tags are elongated structures. Bend the antenna, pierce it or cover it with metal and you lose range.
Substrate and inlay
Chip and antenna sit on a carrier film, usually PET film or paper. This unit is called an inlay and is the semi-finished product from which every other form factor is made. A dry inlay is the bare film, a wet inlay already carries a layer of adhesive. Only the converting step turns it into a label, a hangtag or a hardtag.
- Chip area
- under 1 mm²
- EPC memory
- 96 to 496 bits, depending on the chip
- Antenna length
- around 70 to 100 mm at 868 MHz
- Thickness
- inlay around 0.1 mm, finished label 0.2 to 0.4 mm
- Weight
- under 1 gram
- Power source
- none — the field of the reader
- Service life
- no battery, so effectively unlimited
Passive, semi-passive, active
RFID tags are grouped by the way they are powered. Passive tags have no battery, cost a few cents and are read from a few centimetres up to around 12 metres, depending on the frequency. Semi-passive tags carry a battery for the chip electronics but still answer passively. Active tags transmit with their own energy and reach 50 metres and more, but cost many times as much and live only as long as their battery.
| Type | Power | Range | Price each | Typical use |
|---|---|---|---|---|
| Passive | from the reader field only | a few cm up to approx. 12 m | approx. €0.04–0.20 | retail, logistics, libraries, access control |
| Semi-passive (BAP) | battery for the chip, passive reply | approx. 20–100 m | approx. €5–30 | temperature logging, cold chain, sensors |
| Active | battery, transmits on its own | approx. 50–500 m | approx. €15–80 | containers, vehicles, large plant and equipment |
Price and range figures are guide values for the European market and vary considerably with the application, the form factor, the chip and the order quantity.
For a shop the decision is quickly made: only passive tags are cheap enough to go on every single garment. A shop with 4,000 items would end up in five figures with active tags at 15 euro each, and at around 500 euro with passive labels. Semi-passive and active tags play to their strength where a small number of expensive, moving objects is involved — or where readings have to be recorded over time.
LF, HF and UHF — and why retail uses UHF
RFID works in three frequency ranges: LF at 125 to 134 kHz, HF at 13.56 MHz, and UHF, which in Europe occupies the 865 to 868 MHz band under ETSI EN 302 208 and in the United States 902 to 928 MHz. LF and HF couple through a magnetic field and reach a few centimetres up to about a metre. UHF couples through an electromagnetic field, reaches several metres and can record hundreds of tags at once — which is why UHF is the standard in retail.
| Band | Frequency | Read range (passive) | Standards | Typical use |
|---|---|---|---|---|
| LF | 125–134 kHz | up to approx. 10 cm | ISO 11784/11785, ISO 18000-2 | animal identification, access control, immobilisers |
| HF | 13.56 MHz | up to approx. 1 m | ISO 14443, ISO 15693, NFC | ID cards, tickets, libraries, payment cards |
| UHF (EU) | 865–868 MHz | approx. 1–12 m | ETSI EN 302 208, ISO 18000-63 | retail, logistics, stocktaking |
| UHF (US) | 902–928 MHz | approx. 1–15 m | FCC Part 15, ISO 18000-63 | the same applications, a different band |
Why UHF won in retail
Four reasons, in this order:
- Bulk reading. The anti-collision procedure in EPC Gen2 lets hundreds of tags a second answer one after another. A full rail is counted in seconds.
- Range without line of sight. A handheld reads through boxes, stacks and closed drawers. With a barcode every item has to be picked up.
- Price. UHF inlays are made in their billions. No other auto-ID method that identifies individual items is currently as cheap per object.
- One standard worldwide. EPC Gen2, or ISO 18000-63, is the same protocol from the brand through the distributor to the shop.
The different bands in Europe and the United States are no obstacle in practice: modern chips and antennas are laid out as worldwide-band versions and work from 860 to 960 MHz. One difference does remain: in Europe the radiated power is capped at 2 watts ERP under ETSI EN 302 208, while in the United States 4 watts EIRP are permitted. Range figures from American datasheets therefore cannot be carried over one to one to a European shop.
Inlay, label, hangtag, laundry tag, hardtag, on-metal
Every form factor holds the same core element, an inlay of chip and antenna, but they differ in how they are converted and how robust they are. Clothing is dominated by self-adhesive labels and hangtags at around 12 to 15 cents; rented linen uses washable textile tags, article surveillance uses reusable hardtags, and metal objects need on-metal tags with a spacer.
| Form factor | Construction | Range | Price each | Typical use |
|---|---|---|---|---|
| Inlay (dry/wet) | chip and antenna on PET or paper film, no top layer | 3–8 m | approx. €0.04–0.10 | semi-finished goods for label converters, lamination into cards |
| Self-adhesive label (smart label) | wet inlay between thermal paper and adhesive, printable | 3–8 m | approx. €0.12–0.15 | price label, carton marking, stockroom |
| Hangtag (swing ticket) | card or plastic with an inlay inside, with an eyelet | 4–10 m | approx. €0.12–0.20 | clothing, footwear, accessories |
| Laundry tag (textile tag) | inlay sealed into silicone or fabric, washable | 1–3 m | approx. €0.40–1.50 | rented linen, workwear, hotels, clinics |
| Hardtag | plastic housing with a pin, often with an EAS function, reusable | 4–8 m | approx. €0.80–2.50 | article surveillance, high-value fashion |
| On-metal tag | inlay with a ferrite layer and a spacer, often in a rigid housing | 1–6 m | approx. €0.50–5.00 | tools, machinery, IT equipment, gas cylinders |
Guide values for the European market at small to medium order quantities, net of VAT, without printing and encoding. Ranges measured with ordinary UHF handhelds under favourable conditions — on the shelf, between goods and near metal they are lower.
The choice of form factor almost always comes down to three questions. Does the tag stay on the product or is it removed? Does it have to survive water, heat or mechanical load? And does it sit on or near metal? In fashion the answer is usually: removable, no particular load, no metal — so a cheap paper label or a hangtag.
EPC Gen2, UCODE and what is stored on the tag
Passive UHF tags in retail follow the EPC UHF Gen2 air interface protocol from GS1, standardised internationally as ISO/IEC 18000-63. The chip memory is split into four banks: a reserved area for the kill and access passwords, the EPC memory holding the object number itself, the unchangeable TID with the manufacturer and chip identifier, and optionally a freely writable user memory.
EPC Gen2 and ISO 18000-63
Gen2 governs how reader and tag talk to each other: how the tag is woken, how collisions are resolved when many tags answer at the same time, how data is written, locked and permanently disabled. Because the protocol is open and identical worldwide, a label from manufacturer A works with a reader from manufacturer B. That is the practical reason why buying labels does not tie you to one hardware supplier.
Chip families
A small number of chip families dominate the market. The best known is UCODE from NXP, currently in the UCODE 8 and UCODE 9 generations, alongside Impinj chips from the Monza and M700 lines and Higgs from Alien. The differences lie in sensitivity, memory size and extra functions — built-in self-tests, for instance, or an indication of whether a tag has already been read. For fashion retail those differences are secondary; what matters is that the chip is Gen2 compliant.
TID, EPC and user memory
- Reserved: kill password and access password, 32 bits each. The kill password switches a tag off irreversibly.
- EPC: the object number written during encoding. It can be changed for as long as it has not been locked.
- TID: assigned by the chip manufacturer, write protected. It holds the manufacturer and model identifier and, on many chips, a globally unique serial number as well. That makes it possible to check whether a tag has been cloned.
- User memory: optional free memory, from 32 to several hundred bits depending on the chip. In retail it is usually unused.
SGTIN-96
For retail goods the EPC memory usually holds an SGTIN-96: a 96-bit Serialised Global Trade Item Number. It is made up of the GS1 company prefix, the item reference and a serial number. That serial number is precisely the difference from a barcode. An EAN barcode says “trousers, model X, size 32”. An SGTIN says “this one pair of trousers, model X, size 32, piece number 000147”. That is why RFID can count not only how many items are there, but also whether one particular item is still there.
If you have no GS1 number capacity of your own, an internal numbering scheme will do. For the closed loop inside a single shop that is enough. As soon as tags are exchanged with suppliers or platforms, the GS1-compliant SGTIN is the safer route.
What RFID labels cost
Passive UHF labels cost around 12 to 15 cents each in small quantities, that is when single rolls are bought. Large buyers with five-figure annual volumes pay under 5 cents. Special form factors such as washable laundry tags, hardtags or on-metal tags run from 40 cents to several euro each, depending on the version.
Five factors essentially set the price:
- Order quantity. The biggest lever. Between a roll of 1,000 pieces and an annual volume of 500,000 pieces there is easily a factor of three.
- Form factor. A paper label is a mass-produced article; a sealed laundry tag is an industrial product with several manufacturing steps.
- Chip and antenna size. Larger antennas cost more material, more sensitive chips more licence fee.
- Printing and encoding. Pre-printed and pre-encoded from the supplier is convenient, but dearer and inflexible. If you work with an RFID printer yourself, you buy blank labels.
- Converting. Special formats, perforations, eyelets or unusual adhesives each add a few cents.
For a shop the simplest calculation is the right one: labels are consumables and fall due once per item. A shop with 4,000 items in stock pays around 480 euro to label its existing stock at 12 cents each. After that only new goods cost anything — with 6,000 items bought in over a year, about 720 euro. That is an order of magnitude that sits comfortably alongside price tickets and label printing.
All prices are net guide values for the European market in 2026 and exclude VAT; business buyers elsewhere in the EU holding a valid VAT identification number are invoiced under the reverse-charge procedure. Figures can vary with the application, the supplier and raw material prices.
Metal, liquids and misreads
RFID has physical limits. Metal reflects UHF radio waves and detunes the tag antenna; water and products containing water absorb the energy, so a standard label directly on metal or on a full bottle often does not answer at all. On top of that come misreads from shadowing in dense stacks of goods, and phantom reads from neighbouring rooms.
Metal
A conductive surface directly behind the antenna all but cancels the field. Stick a standard label flat on sheet metal and the range often drops to zero. On-metal tags are the remedy: they carry a ferrite or foam layer as a spacer and use the metal surface as part of the antenna. They cost many times as much and are thicker.
Liquids
Water absorbs strongly in the UHF range. Drinks, cosmetics, cleaning products and damp goods weaken the signal. Wet clothing also reads worse than dry. In such cases the tag is offset to one side, set on a spacer, or the system moves to HF, which is less sensitive to water.
Overlap and bulk reading
When very many tags answer at the same time, collisions occur. Gen2 resolves this with a slot procedure in which every tag picks a time slot at random. It works well, but it costs time: the denser the crowd, the more passes the reader needs. Tightly packed goods in a carton therefore read more slowly than loosely hanging goods on a rail.
Misreads in both directions
- Missing reads come from shadowing: an item lies at the very bottom of a stack, behind a mirror, or right against a metal shelf.
- Phantom reads occur when the device picks up tags from the next room, the window display or the shop next door. The remedies are reduced transmit power, directional antennas and a clean split into zones.
In practice, read rates per pass on tagged clothing typically run between 97 and over 99 per cent, depending on the set-up and the way you work. If you need the last tenths, you walk the room a second time or count critical zones by hand. No serious supplier guarantees a hundred per cent.
What to watch for in fashion retail
In fashion retail the RFID tag sits either in the swing ticket or as a label in the hem or on the care label. The swing ticket is torn off at the point of sale; a sewn-in label stays with the garment and has to be deactivated instead, or booked as sold in the software. Either way only a number is stored on the tag, no customer data.
Placement
The simplest option is the hangtag: the label goes on together with the price ticket, hangs free in the air and reads excellently. It leaves the garment automatically at the point of sale. If you also want to follow goods in the fitting room and in circulation, you put the label into the hem or on the care label instead — that is less conspicuous, but the range drops because the label lies between layers of fabric.
On footwear the tag is stuck into the box or laid into the lining. On accessories with metal parts, belt buckles or jewellery for instance, leave at least a few millimetres between the tag and the metal.
Deactivation at the point of sale
- Removal: swing ticket off, label gone. The simplest and cheapest way.
- Kill command: the tag is switched off irreversibly by a Gen2 command. It never answers again. This needs the kill password and a device at the till.
- Status change: the article is booked as sold in the stock software. The tag still transmits, but is ignored when counting. In systems such as HANGCOUNT this is the usual route, because it needs no extra hardware at the till.
Data protection
A retail tag holds a number — typically an SGTIN made up of an item number and a serial number. Neither name nor address nor purchase history sits on the chip. A link to a person in the sense of the GDPR only arises once that number is brought together with customer data in a system, through a loyalty card for example. If you do not do that, RFID processes no personal data.
Even so: tags that leave the shop on the product should be recognisable to customers. GS1 and consumer bodies recommend marking the label visibly and explaining how it can be removed or deactivated. That takes little effort and takes the heat out of the discussion.
Common questions about RFID tags
What is an RFID tag?
An RFID tag is a data carrier that transmits a stored number by radio to a reader. It consists of a microchip, an antenna and a carrier material. Passive tags have no battery: they draw their energy from the radio field of the reader and answer for as long as they are inside that field.
What does an RFID tag cost in Europe?
A passive UHF label costs around 12 to 15 cents each in small quantities, that is when single rolls are bought. Large buyers with five-figure annual volumes pay under 5 cents. Special form factors such as washable laundry tags or on-metal tags sit well above that, running from 40 cents to several euro depending on the version. All prices are net and exclude VAT.
What read range does an RFID tag have?
On passive UHF tags in the European 865 to 868 MHz band the practical read range is between about 1 and 12 metres, depending on antenna size, reader and the surface underneath. HF tags at 13.56 MHz read up to around a metre, LF tags at 125 kHz only a few centimetres. Active tags with a battery of their own reach 50 metres and more.
What is the difference between an RFID tag, an RFID label and a transponder?
The terms mean the same component in different converted forms. Transponder is the technical umbrella term, from transmitter and responder. Tag denotes the finished data carrier in any form factor. Label means the self-adhesive, printable version, in which an inlay sits between paper and adhesive.
Why does retail use UHF and not NFC?
UHF tags in the 865 to 868 MHz range can be read in bulk: a handheld records hundreds of labels a second from several metres away, with no line of sight. NFC works at 13.56 MHz with a few centimetres of range and is meant for single lookups, not for recording a whole rail of goods.
Can an RFID tag hold personal data?
A retail tag normally holds only a number, usually an SGTIN to the GS1 standard made up of an item number and a serial number. Name, address and purchase history are not on the tag. A link to a person only arises once that number is connected to customer data in a system, and the usual requirements of the GDPR then apply.
Do metal and liquids interfere with reading?
Yes. Metal reflects the radio waves and detunes the tag antenna; water and products containing water absorb energy in the UHF range. A standard label directly on metal is often not read at all. For such cases there are on-metal tags with a spacer and a ferrite layer that use the metal surface as part of the antenna.
Does the RFID label have to be removed at the point of sale?
Not necessarily, but it has to disappear from stock. In practice there are three routes: the label is torn off with the swing ticket, it is permanently deactivated by a kill command, or the article is booked as sold in the software and ignored the next time you count. Which route fits depends on the shop concept.
Want to know what this means for your shop?
HANGCOUNT provides RFID stock control for fashion shops, boutiques and sports retailers: software from 99 euro per month per location, plus 2,900 euro once for the RFID printer and handheld. Labels are charged as used. All prices are net and exclude VAT; business buyers elsewhere in the EU holding a valid VAT identification number are invoiced under the reverse-charge procedure.