HID® Prox H10304 (37-Bit with Facility Code) Compatible Cards & Fobs
The structured 37-bit format: a 16-bit facility code (up to 65,535 sites) plus a 19-bit card number (up to 524,287 per site) on the 125 kHz HID Prox platform — 26-bit's layout, scaled for enterprises.
Does American Key Cards make HID Prox H10304 (37-Bit with Facility Code) compatible cards?
Yes — American Key Cards supplies unbranded HID Prox H10304 (37-Bit with Facility Code) compatible cards and key fobs (AKC H10304-Compatible 37-Bit Card), encoded to your facility code and card-number range and ready to use on your existing HID readers. No hardware changes and no dealer account required.
- 125 kHz
- Frequency
- 125 kHz prox
- Technology
- 1
- Bit format
- 4+
- OEM part nos.
- American Key Cards
- Order from
H10304 keeps the facility-code discipline that administrators like about 26-bit and removes its ceilings: 65,535 possible facility codes instead of 255, and 524,287 card numbers under each instead of 65,535. Multi-campus organizations use the facility code as an organizational handle — one code per site, per business unit, or per building — while the expanded card-number field means a single site essentially never runs out. Like all Prox-family formats, the intelligence is in the panel configuration rather than the reader, so replacement ordering never touches hardware. We manufacture unbranded, compatible-by-specification H10304 credentials programmed to your facility code and number range, verified against the published 37-bit layout — one leading parity bit, 16-bit facility code, 19-bit card number, one trailing parity bit — before they leave the bench.
HID Prox H10304 (37-Bit with Facility Code) specifications
- System brand
- HID Global / ASSA ABLOY
- Technology
- 125 kHz Passive Proximity
- Frequency
- 125 kHz
- Credential platform
- 125 kHz low-frequency proximity platform (HID Prox line)
- Bit formats
- 37-bit Wiegand (1 parity + 16-bit facility code + 19-bit card number + 1 parity)
- OEM part numbers
- 1386, 1326, 1346, 1586
Specifications reviewed August 2026
Our compatible HID Prox H10304 (37-Bit with Facility Code) credentials
American Key Cards manufactures unbranded credentials engineered to work with your existing HID 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 HID, and we never supply OEM-branded product — for brand-original credentials, order from HID or an authorized dealer. Brand names appear only to identify compatibility, and all trademarks remain the property of their respective owners.
Where HID Prox H10304 (37-Bit with Facility Code) is used
- Multi-site enterprises needing more facility codes than 26-bit allows
- Healthcare networks
- University systems with many buildings
- Facilities migrating from 26-bit that want structured facility-code management
Works with these readers
Related formats
You might also need
HID 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 cardsHID Prox H10302 (37-Bit, No Facility Code)
The flat-numbering 37-bit format: a single 35-bit card number — over 34 billion unique values, no facility code — on the 125 kHz HID Prox platform, built for enterprises that outgrew 26-bit.
View compatible cardsKantech ioProx (XSF / 26-bit)
Kantech's dual-personality credential: the proprietary XSF format for EntraPass systems and a standard 26-bit Wiegand encoding on the same card — one credential that speaks both languages, all over North American commercial buildings.
View compatible cardsHID Prox H10304 (37-Bit with Facility Code) — FAQ
How many facility codes and card numbers does H10304 support?
Up to 65,535 facility codes, each with up to 524,287 card numbers. That is 256 times the facility-code space of 26-bit and eight times the per-site card capacity, which is why large multi-site systems standardize on it.
Is H10304 backward compatible with 26-bit readers?
The readers are the same 125 kHz Prox family, so the hardware is shared — but a panel expecting 26-bit input will not parse a 37-bit stream, and vice versa, unless it is configured for multiple formats. Your system runs whichever format it was commissioned on; replacements simply match it.
Why would I choose H10304 over H10301?
Scale with structure. If you manage several sites and want each to keep its own facility code — with far more card numbers under each — H10304 is the natural upgrade path from 26-bit while keeping the same reader infrastructure and administrative model.
What do you need from me to program a batch?
Your 16-bit facility code and the card-number range to issue. Both live in your access-control software; if you only have a sample card, send photos of the printed numbers and we will confirm the encoding before production.