Gallagher / Cardax Cards Explained: Cardax IV & MIFARE Tiers

Gallagher and the Cardax Heritage

Gallagher Security, headquartered in New Zealand, grew its access-control product line through the acquisition of Cardax International in the early 2000s. The Cardax IV proximity format — a 125 kHz read-range credential — was already deployed across thousands of commercial and government sites in Australia, New Zealand, and Southeast Asia before the rebrand. Gallagher retained the encoding structure and continued manufacturing hardware that reads it, so installed bases from the Cardax era remain live in many facilities today.

That longevity creates a practical challenge for facilities managers: Cardax IV cards are not interchangeable with standard 26-bit Wiegand credentials. A site running Gallagher controllers with Cardax IV readers cannot simply order generic proximity cards and program them — the region code and proprietary encoding must match the reader's configuration exactly. Understanding that distinction is the starting point for sourcing any Gallagher compatible proximity card that will function correctly on arrival.

Cardax IV LF Format: Region Code, Facility, and Card Number

The Cardax IV data structure transmitted at 125 kHz consists of three fields. The region code is a 4-bit value that maps to one of sixteen letters — A through P — and was assigned geographically by Cardax during initial deployment. Most Australasian installations carry region code A or B, while other markets may see C through F. The facility/event code is 16 bits wide, giving a range of 0 to 65,535. The card number field follows, also 16 bits, allowing up to 65,535 unique card numbers per facility per region. Unlike the ubiquitous 26-bit Wiegand format, which uses an 8-bit facility code, this structure gives Gallagher administrators far finer segmentation of large, multi-site deployments.

On the physical substrate, the Cardax IV encoding is reproduced using write-once or rewriteable LF chips — T5577, EM4305, and Q5 emulation chips are all compatible carriers. The chip simply stores the bitstream; the reader decodes it via the Cardax IV framing. A correctly encoded Gallagher compatible proximity card with a confirmed region code and facility assignment will read identically to an original Cardax-era credential on every controller that supports the format. This is the well-understood, operationally straightforward end of the Gallagher credential family.

Sourcing these LF cards requires knowing three parameters: the region code letter, the facility/event code, and the card number range. Facilities staff can typically recover these from their access-control software database or from an existing card's reader output via the controller's diagnostic log. If the site database has been lost, reading an active credential against a connected controller and inspecting the decoded Wiegand output will surface the full triplet. Our guide on Corporate 1000, FlexSecur and custom facility codes covers the process of recovering and confirming proprietary format parameters in more detail.

The MIFARE and DESFire Secured Generation

Contemporary Gallagher Command Centre installations issue 13.56 MHz smart credentials rather than LF proximity cards for new deployments, though most sites continue to accept LF credentials in parallel during a transition period. The HF tiers use genuine NXP silicon — MIFARE Classic 1K, MIFARE Plus, or NXP DESFire EV2/EV3 chips — personalised with a site-specific diversification key that Gallagher's Card Technology Manager (CTM) software writes during credential issuance. The reader authenticates the chip's sector or application before granting access; a credential without the correct key structure will not authenticate.

This architecture is documented in Gallagher's own technical literature and is consistent with how any serious enterprise access-control platform handles 13.56 MHz credentials. The MIFARE family explained guide covers the cryptographic distinctions between Classic, Plus, and DESFire in detail. The practical implication for procurement is that the HF tiers cannot be pre-encoded with a facility code the way LF cards can, because the diversification key is generated by and held within the specific Gallagher CTM instance managing that site. Compatible HF credentials are therefore supplied as enrolled-blank substrates: the correct NXP chip type, the correct physical format, ready for the site's own CTM to write its keys and credential data.

Gallagher also supports MIFARE Plus in Security Level 3, which provides AES-encrypted sector communication. DESFire EV3 deployments are increasingly common in high-assurance government and critical-infrastructure installations where the AES-128 cryptography and Common Criteria certification of the chip itself are a specification requirement. For sites in this tier, the Gallagher Cardax compatible card we supply is built on genuine NXP DESFire EV3 silicon, formatted to Gallagher's expected application structure, and delivered unkeyed for site enrolment.

Compatible LF Cards vs Compatible HF Blanks: Practical Differences

The procurement workflow differs substantially between the LF and HF tiers, and conflating the two leads to orders that cannot be deployed. For LF Cardax IV, we supply cards encoded to order: you provide the region code, facility/event code, and desired card number range, and the cards arrive ready to assign in the controller. No on-site programming is needed. This is the same workflow used by any access-control integrator ordering standard proximity stock, and it applies equally to key fobs and clamshell credentials.

For HF MIFARE Classic and DESFire tiers, the workflow is different. We supply the correct chip substrate — built on genuine NXP silicon in the physical form factor your Gallagher reader expects — but the credential data and diversification key are written by your site's Card Technology Manager software during normal issuance. From the site administrator's perspective, the compatible blank drops into the existing CTM workflow exactly as a Gallagher-branded blank would. The distinction matters for ordering: HF blanks are ordered by chip type and physical format, not by facility code. Our compatible vs genuine access cards guide explains the enrolled-blank model for secured HF formats in plain terms for procurement teams comparing costs.

The enterprise proprietary formats category includes several other brands with analogous tier structures — Lenel 42-bit compatible cards, Avigilon compatible cards, and Software House CCOTZ 37-bit compatible cards all follow a similar LF-encodable or HF-blank split. If you manage a multi-brand estate, the same supply logic applies across all of them.

Ordering a Compatible Gallagher Credential

For LF Cardax IV orders, the minimum information required is: region code (letter A–P), facility/event code (0–65535), and the card number range. Most procurement contacts can source this from their Gallagher Command Centre site database under the credential template in use. If the site runs multiple regions or facility codes — common in large multi-tenanted buildings — each block is ordered separately and clearly labelled in our production queue. Standard card and clamshell fob form factors are available in PVC credit-card size (ISO/IEC 7810 ID-1), 26-bit fob, and thin clamshell variants. All LF substrates carry T5577 or EM4305 chips capable of reliably emitting the Cardax IV bitstream at standard proximity read range (typically 5–15 cm depending on reader antenna).

For HF blanks, specify the chip tier: MIFARE Classic 1K, MIFARE Plus SL3, or NXP DESFire EV3. Match the chip type to what your Gallagher Command Centre licence and reader firmware support — this is visible in the CTM credential template configuration. Card stock arrives in Gallagher-standard CR80 format, white or pre-printed to your specification, with no credential data written. Enrolment proceeds through CTM exactly as with OEM stock. The Gallagher / Cardax compatible cards and fobs solution page lists available SKUs across both the LF and HF tiers with per-format ordering notes.

Both LF and HF orders can be fulfilled with custom printing — facility branding, employee photo-ID artwork, barcode, or sequential numbering. LF orders can also include pre-encoded sequential card numbers with a supplied data file. For access-control integrators managing multiple Gallagher sites with different region and facility assignments, bulk orders with mixed encoding runs are supported with a per-block specification sheet. Contact our technical sales team to confirm your site parameters and receive a format-matched sample before committing to a full production run.