What Is the H10320 Clock and Data Card Format and Where to Find More Cards

When it comes to legacy access control systems, the H10320 clock and data card format remains a widely used and trusted solution. Designed for compatibility with many older security infrastructures, this format continues to serve businesses that rely on reliable, low-frequency proximity technology. If you're managing a system that uses the H10320 format, understanding how it works and where to source compatible cards is essential.

Understanding the H10320 Clock and Data Format

The H10320 format is a proprietary 37-bit card format originally developed by HID. Unlike the more common Wiegand formats (like H10301 26-bit), H10320 uses a clock and data output, typically found in older HID readers and controllers.

Key Features of H10320:

• Bit Length: 37 bits
• Encoding Method: Clock and Data (not Wiegand)
• Facility Code Range: 0 to 65,535
• Card Number Range: 0 to 524,287
• Compatibility: HID Prox series readers and systems that support clock and data interfaces

Due to its large range of unique card numbers, H10320 is ideal for organizations that need many unique credentials or want a higher level of security than standard 26-bit cards.

Why Some Systems Still Use H10320 Cards

Many commercial buildings, schools, and industrial sites installed HID clock and data systems over a decade ago. These systems were built to last—and they did. As a result, the H10320 format is still in use in:

• Legacy access control systems
• High-security government or enterprise environments
• Organizations needing long-range credentialing
• Installations where Wiegand is not supported

If your system is hardwired for clock and data output, switching to Wiegand could require replacing readers, controllers, and possibly wiring. That’s why many continue using H10320-compatible proximity cards.

Where to Find More H10320-Compatible Cards

If you're searching for H10320 clock and data proximity cards, you need a supplier that understands format integrity, bit structure, and compatibility. A great source for high-quality H10320 cards is:

Authoriz-ID.com

They offer:

• Pre-encoded H10320 cards
• Bulk order discounts
• Fast U.S. shipping
• Optional printing or adhesive labeling
• U.S.-based technical support to help ensure compatibility with your access system

Whether you need 10 cards or 1,000, Authoriz-ID provides options to match your format and facility code requirements.

Final Thoughts

The H10320 clock and data card format remains a critical part of many legacy security systems. If you're using readers or controllers that require clock and data communication, sticking with H10320-formatted cards is a smart and cost-effective choice.

Finding the right supplier ensures your system continues to function smoothly, without the need for expensive hardware upgrades. Be sure to choose a vendor that offers format-accurate, durable, and properly encoded cards—like Authoriz-ID.com.

Need help selecting the right format or encoding for your H10320 cards? Reach out to a credential specialist to ensure full compatibility with your access control system.

Find our selection of H10302 Clock and Data credentials here!