125 Khz Or 13.56 Mhz Credentials?

Dear Team,

I need an advice from IPVM, for choosing the credential format for a newly building hospital.

Among 125 KHz Credential or 13.56 MHz credentail , which will be an ideal one?

Is it a wise decision to go for Multicard supported reader in this scenario?

Our Favorite Access Control Credentials report covers this in depth.


"A proximity reader whoch suppports 31 bits or equivalent format and that is readily avaialbale in and not proprietary to any manufacturer or vendor"

Is it means 125Khz card and reader can support multiple technologies

Is it means 125Khz card and reader can support multiple technologies

No: 125 kHz readers work with 125 kHz cards, but not 13.56 MHz products.

Also, the reader/controller itself may be 'locked out' to read only certain formats or facility codes, so you cannot generally guarantee interoperability of even 125 kHz cards.

For contactless cards, 'Multiple technology' readers read different frequencies. (Both 125 kHz AND 13.56 MHz.)

Is there a specific product you're looking at? It might help clarify some of your questions to look specifically at it here.

I just wants to understand this statement about the reader which I found in one of the ACS document

" A proximity reader which supports 31 bits or equivalent format and readily available and not prorietary to any manufacturer or vendor"

" A proximity reader which supports 31 bits or equivalent format and readily available and not prorietary to any manufacturer or vendor"

This is asking for a 3rd-party 125 kHz reader that can be used with 31-bit cards.

The good news: this is pretty easy to find. If you find a Prox or ProxII format reader that connects via Weigand to a controller at your local distributor or online, it should work. This meets the 'readily available, not proprietary to any mfg/vendor' part.

In many parts of the world, HID Global is a common brand of this type of reader.

A 'multiclass' reader would work too. It would be able to read both 13.56 MHz and 125 kHz credentials.

13.56 MHz (Mifare) indeed offers higher security than "plain-vanilla" 125 KHz stuff (which is very old techology that has been around since the 1990s); but for really REALLY HIGH security requirements, NOT even 13.56 Mifare is enough.

You are not saying how secure the new hospital facility demands in their request for proposals, but I guess that if it is a military/federal site with strict clearances requirements, you may consider DESfire for really serious mutual authentication (meaning that it has AES 128, DES/Triple-DES Data Encryption with Unique 56-Bit Serial Numbers).

Thanks a lot for your replies.

As mentioned in Brian's reply ,I wish to know the classification of cards based on the number of bits used for the communication .

Some body help me

The correlation between credential bits and a particular card technology is very weak.

For example, despite being capable of so much more, you will find 26 bit 13.56 MHz 'smartcards' are available.

In summary: card technology is not a function of credential bits.

Aren't the 125khz passive prox cards typically limited to under 38 bits?

I know that (125 KHz) HID C10106 Formats are at least 40 bit, and I think there might even be bigger ISO formats in that frequency range.

Agreed (now), I found some that were 64-bit. Thanks.

In my defense wiki said this

The physical size limitations of the card dictated that a maximum of 37 Wiegand wire filaments could be placed in a standard credit card, as dictated by CR80 or ISO/IEC 7810 standards, before misreads would affect reliability. Therefore, most Wiegand formats used in physical access control are less than 37 bits in length.

Is my problem that 125kHz does not necessarily imply 'Wiegand format'?

There is confusing ambiguity in that Wiki article, because 'wiegand cards' are antiques and not the same as 'Wiegand Protocol' that is still in widespread use, for 125 kHz or even 13.56 MHz credentials:

Essentially a wiegand card used 37 short wire segments, each tuned to read a different bit value when scanned by a reader. It is still contactless (not optical like a barcode), but it was rapidly outclassed by 125 kHz resonant-powered cards. (Which in turn have been outclassed by 13.56 MHz cards.)

The exact number of wire segments varied. In the beginning, it was only 26 (ie: 26 bit). The physical size of the card limited the tech to about 37 in widespread use, although you can find whitepapers online that describe the possibility for bigger values.