EM4102 (64-bit Read-Only Variant) Compatible Cards & Fobs
EM4100's identical twin: EM4102 transmits the same 64-bit read-only protocol, so the two are interchangeable on any EM-protocol reader — a detail worth knowing so you don't overthink a reorder.
Does American Key Cards make EM4102 (64-bit Read-Only Variant) compatible cards?
Yes — American Key Cards supplies unbranded EM4102 (64-bit Read-Only Variant) compatible cards and key fobs (AKC EM4102-Compatible Clamshell Card), encoded to your facility code and card-number range and ready to use on your existing EM Microelectronic readers. No hardware changes and no dealer account required.
- 125 kHz
- Frequency
- RFID prox
- Technology
- 1
- Bit format
- 2+
- OEM part nos.
- American Key Cards
- Order from
EM4102 exists mostly as a manufacturing designation: for the purpose that matters to a facility — reading on the doors — it is protocol-identical to EM4100 and drops into the same systems without a second thought. Datasheets distinguish them at the silicon level, but a reader sees the same 64-bit Manchester-encoded ID either way, which is why suppliers and integrators use the names almost interchangeably. Practically, that means if your paperwork says EM4102, EM4100, TK4100, or H4102, you're in one compatible family. We supply unbranded EM4102-compatible cards and key tags programmed to your system's IDs and verified before shipping; if you're not sure which exact variant your readers were sold with, it rarely matters, and we'll confirm it from a sample if you want certainty.
EM4102 (64-bit Read-Only Variant) specifications
- System brand
- EM Microelectronic-Marin SA
- Technology
- Passive RFID proximity
- Frequency
- 125 kHz
- Credential platform
- EM4102 read-only IC: functionally identical to EM4100, 64-bit factory-programmed ROM, ASK/Manchester, full EM4100-reader compatibility
- Bit formats
- 64-bit EM4100/EM4102 protocol (identical transmission): 9 header bits + 40 data bits + 14 parity bits + 1 stop bit
- OEM part numbers
- EM4102, H4102 (compatible IC)
Specifications reviewed August 2026
Our compatible EM4102 (64-bit Read-Only Variant) credentials
American Key Cards manufactures unbranded credentials engineered to work with your existing EM Microelectronic readers — no hardware changes, encoded to your facility code and card-number range before they ship.
Full specifications, form factors and ordering FAQ: Standard 125 kHz proximity cards
American Key Cards is an independent manufacturer of unbranded, compatible-by-specification credentials. We are not affiliated with, endorsed by, or sponsored by EM Microelectronic, and we never supply OEM-branded product — for brand-original credentials, order from EM Microelectronic or an authorized dealer. Brand names appear only to identify compatibility, and all trademarks remain the property of their respective owners.
Where EM4102 (64-bit Read-Only Variant) is used
- Legacy EM4100/EM4102 reader-system replacements
- Time-and-attendance and visitor management
- Basic building access in residential and light commercial
- Parking and recreational facility entry
Works with these readers
Related formats
You might also need
EM4100 (64-bit Read-Only)
The world's baseline 125 kHz credential: EM4100's 64-bit read-only ID, transmitted in Manchester-encoded ASK, is what most simple prox systems, time clocks, and gym doors actually run on.
View compatible cardsEM4200 (128-bit Enhanced Read-Only)
EM4100 with more room and more reach: EM4200 offers up to 128 bits and better read range while staying backward-compatible with EM4100 readers in 64-bit mode — plus an ISO animal-ID mode for tagging.
View compatible cardsHID Prox H10301 (Standard 26-Bit)
The most widely deployed proximity format in North America: 26-bit Wiegand — an 8-bit facility code plus 16-bit card number — on the 125 kHz HID Prox platform, live on millions of doors.
View compatible cardsEM4102 (64-bit Read-Only Variant) — FAQ
What's the difference between EM4100 and EM4102?
For access purposes, none that a reader can tell — EM4102 uses the same 64-bit read-only protocol and reads on EM4100 infrastructure identically. The distinction is a chip-generation label, not a compatibility barrier.
Will EM4102 cards work on my existing EM4100 system?
Yes. They're protocol-compatible, so they enroll and read exactly like EM4100 stock. Facilities routinely mix the two without any configuration change.
How do I reorder to match my current credentials?
Send your enrolled-ID list from the access software or photos of working cards (the ID is often printed on them). We program compatible stock to those IDs and verify before shipping.
I have a mix of EM4100 and EM4102 cards — is that a problem?
Not at all. They're one compatible family on EM-protocol readers, so a mixed fleet behaves as a single population. New compatible stock joins it seamlessly.