Replacement RFID Cards: How Do I Know Which Cards to Order?
To order the right replacement RFID cards, you need to match the card to your existing access control system. Different technologies aren't interchangeable: you'll need to know the chip type and frequency used by your particular system, and in some cases the card number format.
Ordering RFID cards can be confusing because two cards can look almost identical but work completely differently.
One may open your office door, while another does absolutely nothing. Helpful? Not really. Common? Very.
Know which RFID cards you need?
If you already know the card type and chip, search our RFID card range by technology. We also provide custom branded RFID cards, in PVC, ECO-PVC and Wood/Bamboo.
What to check before ordering replacement RFID cards
The best place to start is with your existing card, fob, reader or access control system. You're looking for any identifying names, marks or credentials that can give you some clues. This can be difficult if your card is custom printed or plain white.
In this case you'll want to look closely at the readers you're using (what you tap your card against), and any literature or user manuals for that reader.
Useful details to look for
- The access control system or reader on the wall often has the brand, make and model number printed on it. You can then look up the user manual online for information about the cards it works with
- Any logos, numbers or letters printed on the card. Many manufacturers print the operating frequency on the front or back of the card
- Any wording such as MIFARE, DESFire, EM, HID, Paxton, NTAG or ISO numbers.
Or scan the card with your SmartPhone
Most smartphones can only detect 13.56 MHz High Frequency chips. These are the newer chips used in most contactless cards. First, enable your NFC settings. Then install an NFC reader app or RFID card reader app from your appstore and hold the card flat against the back of the phone. It will display the tag type and ID.
This tends to be more straightforward on Android devices, iOS doesn't always give you a detailed breakdown.
Interested in how RFID cards actually do their thing? Read our broader guide: What is an RFID card and how does it work?
Check the frequency: 125kHz or 13.56MHz?
One of the main things to check is the RFID frequency. For the majority of access control cards, the common options are 125kHz and 13.56MHz.
| Frequency | Common card types | Typical uses | What to know |
|---|---|---|---|
| 125kHz | EM4200, proximity cards and some older access cards | Basic door entry and legacy access control systems | Often used for simple proximity access. It is not the same as MIFARE or NFC. Often has a long string of numbers printed on the card. Older technology. |
| 13.56MHz | MIFARE Classic, MIFARE DESFire, MIFARE Ultralight, NTAG | Access control, memberships, hotels, campuses, events and NFC-style applications | More common in smart card applications, but chip type still matters. Usually blank, with no numbers or details printed on the card. |
The frequency matters because a reader is usually designed for one frequency only. For example, it's highly unlikely a 125kHz proximity card would work in place of a 13.56MHz MIFARE card unless the reader supports both technologies.
Check the chip type
Frequency is only part of the answer. You also need to know the chip type. This guide may help you to find the most likely card based on usage, but you'll still need to check for certain.
| Card type | Common use | Best fit | Product link |
|---|---|---|---|
| MIFARE Classic 1K | Most common card used in access control, gyms, memberships and staff cards | Everyday systems using MIFARE Classic technology | View MIFARE Classic 1K Cards |
| MIFARE DESFire | Used for higher-security access requirements - often in education and government | Systems requiring stronger security and more advanced applications | View MIFARE DESFire Cards |
| MIFARE Ultralight | Tickets, events and temporary visitor passes | Short-term or lower-memory applications | View MIFARE Ultralight Cards |
| EM4200 / Proximity | Older or basic door access systems | 125kHz proximity access control | View EM4200 Proximity Cards |
| NTAG / NFC | Smartphone interactions, links, attractions and marketing triggers | NFC-style tap interactions rather than standard door access | View NTAG 216 Cards |
If you are comparing MIFARE options, our guide to the MIFARE family range may help explain the differences in more detail.
Important: card types are not automatically interchangeable. A MIFARE card is not the same as an EM4200 proximity card, and an NTAG card is not automatically suitable for door access. Always check compatibility before ordering.
Will replacement RFID cards work straight away?
Not always. Many access control cards, fobs and tokens need to be enrolled onto your system before they will work. This is usually done through your access control software by your facilities manager, IT team, installer, landlord or building manager.
We can supply compatible RFID cards and fobs, but in many cases the cards still need to be added to your system before they will open doors or activate access.
Common mistakes when ordering replacement access cards
- Ordering by appearance only: two cards can look the same but contain different chips.
- Assuming all RFID cards work with all readers: the reader must support the card technology.
- Confusing NFC with all RFID: NFC is a type of RFID, but not every RFID access card is an NFC card.
- Ignoring the frequency: 125kHz and 13.56MHz cards are not the same.
- Forgetting about enrolment or encoding: some cards need to be added to the system or have data written to them before use.
- Buying the cheapest option without checking compatibility: the cheapest card is not a bargain if it does not open the door.
Still not sure? Ask us for a test card
Get in touch with as much information as you can and we'll send you out a sample card to test before you order.
Replacement RFID Card FAQs
How do I know what RFID card I have?
Start by checking your existing card, fob or key tag for printed details such as the card type, supplier name, system brand, card number or frequency. If nothing is visible, check your access control system records or ask your installer. A photo of the card and reader may also help narrow it down.
Are all RFID cards the same?
No. RFID cards can use different frequencies, chip types and data formats. A card that works with one access control system may not work with another. Common examples include MIFARE, DESFire, EM4200, NTAG and other proximity or smart card technologies.
What is the difference between 125kHz and 13.56MHz RFID cards?
125kHz cards are often used for basic proximity access control systems, while 13.56MHz cards include technologies such as MIFARE, DESFire, Ultralight and NTAG. The reader must support the frequency and card type being used, so it is important to check before ordering replacements.
Will replacement RFID cards work straight away?
Not always. Many access control cards, fobs and tokens need to be enrolled onto the system before they work. This is usually handled by whoever manages your access control software, such as your facilities manager, IT team, installer, landlord or building manager.
Can The Card Network clone my existing key fob?
No, we do not offer key fob cloning or a walk-in copy service. We supply access control cards, fobs and RFID products for businesses to enrol or program onto their own systems where compatible. If you are a tenant in a shared building, you may need to speak to your landlord, building owner or facilities manager.
Do I need blank RFID cards or custom printed RFID cards?
Blank RFID cards are useful if you already encode or enrol cards yourself. Custom printed RFID cards are better if you need branding, staff details, membership information or guest designs printed onto the card. Some customers need both printing and encoding, depending on the system.
