125KHz HID 26 bit RFID Key Tag are now adored by a number of people as they weigh light and are portable to bring it everywhere. It is becoming a fashion stuff these days and making our life more easier. As the technology is moving with a rocket speed and nothing is left untouched with the technical advancement so implies for the 125KHz HID 26 bit RFID Key Tag
125kHz HID 26-bit RFID key tags are among the most widely used credentials for physical access control systems. Designed for durability and portability, these low-frequency RFID tags are commonly deployed in office buildings, residential communities, schools, hospitals, parking facilities, and industrial sites.
What Is a 125kHz HID 26-Bit RFID Key Tag?
A 125kHz HID 26-bit RFID key tag is a low-frequency (LF) passive RFID credential that operates at 125 kHz. It is typically encoded using the HID H10301 26-bit format, one of the most popular credential formats in modern access control systems.
Unlike magnetic cards, RFID key tags communicate wirelessly with compatible readers. Simply holding the key tag near the reader allows the system to identify the credential and determine whether access should be granted.
Because of their compact size and keychain design, RFID key fobs are a convenient alternative to traditional access cards.
Technical Specifications
| Item Name | 125KHz HID 26 bit RFID Key Tag |
| Chip | EM4200/TK4100EM4305/T5577/HID,etc |
| Frequency | 125khz/13.56Mhz |
| Material | ABS |
| Color | Blue/Red/Black/Yellow/Green,etc |
| Size | 36*29*6mm |
| Weight | Around 0.0046kg/pcs |
| Package | 100pcs/poly bag,2500pcs/carton |

Key Features
- Operates at 125 kHz low frequency
- Compatible with HID Prox access control systems
- Available in read-only and rewritable versions
- Waterproof ABS housing
- Compact and lightweight design
- Long service life without battery
- Resistant to dust, moisture, and daily wear
- Multiple colors available
- OEM logo printing and UID numbering supported
- Suitable for indoor and outdoor environments



Understanding HID 26-Bit Format
The HID 26-bit format, also known as H10301, is one of the industry’s most widely adopted access control credential formats.
A standard 26-bit credential consists of:
| Field | Length |
|---|---|
| Leading Even Parity | 1 bit |
| Facility Code | 8 bits |
| Card Number | 16 bits |
| Trailing Odd Parity | 1 bit |
Total length: 26 bits
The Facility Code identifies the organization or site, while the Card Number uniquely identifies each credential within that facility.
This simple structure explains why HID 26-bit cards remain compatible with thousands of access control systems worldwide.
Supported RFID Chips
Different chips provide different capabilities.
| Chip | Type | Rewritable | Typical Use |
|---|---|---|---|
| HID Prox | Original HID | No | Genuine HID credentials |
| EM4200 | Read-only | No | Standard ID tags |
| TK4100 | Read-only | No | EM4100 compatible tags |
| EM4305 | Read/Write | Yes | RFID duplication and programming |
| T5577 | Read/Write | Yes | Multi-format programmable tag |
Read-Only vs Rewritable RFID Tags
| Feature | Read-Only Tag | Rewritable Tag |
|---|---|---|
| Data Modification | No | Yes |
| Security | Higher | Depends on programming |
| Cost | Lower | Slightly higher |
| Programming Required | No | Yes |
| Typical Chips | EM4200, TK4100 | T5577, EM4305 |
For system integrators and RFID developers, rewritable chips such as T5577 and EM4305 provide greater flexibility during testing and deployment.
Compatible Reader Types
These RFID key tags are compatible with many 125kHz readers, including:
- HID Prox readers
- EM4100 compatible readers
- Wiegand output readers
- USB RFID readers
- Standalone access controllers
- Time attendance terminals
- Parking management systems
- Elevator access systems
Compatibility depends on both the RFID chip and credential format programmed into the tag.
Typical Applications
125kHz HID key tags are widely used in numerous industries.
| Industry | Typical Application |
|---|---|
| Commercial Buildings | Employee access control |
| Residential Communities | Gate entry |
| Education | Campus access |
| Healthcare | Staff identification |
| Manufacturing | Restricted area access |
| Parking Facilities | Vehicle entry management |
| Hotels | Staff authentication |
| Gyms & Clubs | Membership identification |
Advantages of HID 26-Bit RFID Key Tags
Reliable Performance
Low-frequency RFID technology performs well around moisture and non-metallic materials, making it suitable for daily access control.
No Internal Battery
Passive RFID tags receive power from the reader, eliminating battery maintenance.
Long Service Life
ABS housings protect the embedded chip against impact and environmental exposure, allowing years of reliable operation.
Fast Authentication
Credential verification typically takes less than one second.
Easy to Carry
The keychain form factor allows users to attach the credential to their keys, reducing the risk of loss.
Available Customization Options
Manufacturers commonly offer:
- Custom logo printing
- Laser engraving
- UID or serial number printing
- Barcode printing
- QR code printing
- Custom colors
- Custom packaging
- Pre-programmed facility code and card numbers
- OEM and ODM services
HID 26-Bit vs Other RFID Technologies
| Technology | Frequency | Typical Range | Memory | Common Use |
|---|---|---|---|---|
| HID 26-Bit Prox | 125 kHz | 2–10 cm | Credential ID | Access control |
| EM4100 | 125 kHz | 2–10 cm | Read-only | Identification |
| MIFARE Classic | 13.56 MHz | 2–8 cm | Yes | Campus cards |
| NTAG213 | 13.56 MHz | 2–5 cm | Yes | NFC marketing |
| UHF EPC Gen2 | 860–960 MHz | Up to 10 m | EPC Memory | Logistics |
Choosing the Right RFID Chip
Consider the following recommendations:
| Requirement | Recommended Chip |
|---|---|
| Standard HID replacement | HID Prox |
| Low-cost access credential | TK4100 |
| Industrial identification | EM4200 |
| RFID testing and development | T5577 |
| Reprogrammable deployment | EM4305 |
Installation and Usage Tips
- Keep the tag clean and free from heavy physical damage.
- Avoid prolonged exposure to extremely high temperatures.
- Do not attach the tag directly to large metal surfaces unless designed for metal environments.
- Verify reader compatibility before deployment.
- Maintain a secure database of assigned card numbers.
Frequently Asked Questions
Is a HID 26-bit RFID key tag the same as a proximity card?
Essentially yes. A HID 26-bit key tag is a compact proximity credential designed for keychain use instead of wallet storage.
Can a T5577 emulate a HID 26-bit tag?
Yes. When properly programmed, a T5577 chip can emulate several common 125kHz credential formats, including many HID-compatible formats.
What is the reading distance?
Typical reading distance ranges from 2 to 10 cm, depending on the reader, antenna design, and installation environment.
Does the key tag require a battery?
No. Passive RFID tags receive power from the electromagnetic field generated by the reader.
Can the facility code be customized?
Yes. For programmable chips or factory-encoded credentials, manufacturers can usually configure custom facility codes and card numbers.
Why Choose a 125kHz HID 26-Bit RFID Key Tag?
The 125kHz HID 26-bit RFID key tag remains one of the most dependable and cost-effective credential solutions for access control. With broad compatibility, durable construction, fast authentication, and support for both read-only and programmable chips, it is suitable for commercial, residential, educational, healthcare, and industrial environments.
Whether you need standard HID-compatible credentials, customizable OEM products, or programmable RFID key fobs for system integration, HID 26-bit RFID key tags continue to provide a reliable solution trusted by organizations worldwide.
Why Choose DO RFID Reader?
DO RFID Reader, a professional manufacturer under D.O RFID Group, has over 15 years of experience in the RFID and NFC industry. We specialize in manufacturing high-quality RFID readers, RFID cards, RFID key fobs, RFID tags, and NFC products for applications including access control, vehicle identification, asset tracking, logistics, and inventory management.
We are committed to delivering reliable products, competitive pricing, fast production, and responsive customer service. Every product is backed by a 3-year warranty, and our technical support team is available to respond within 24 hours. We also provide flexible OEM and ODM customization to meet your specific project requirements.

Get in Touch
Whether you need standard 125kHz HID 26-bit RFID key tags or customized RFID solutions, DO RFID Reader is ready to help. Contact us today for a quote or to discuss your project—we look forward to being your trusted RFID manufacturing partner.

