HID 13.56 MHz (1441 combo: + 125 kHz) Compatible card available

HID FlexSmart MIFARE (1431/1441) Compatible Cards & Fobs

HID FlexSmart is the MIFARE Classic card line — 1431 as a MIFARE-only ISO card, 1441 as a MIFARE + 125 kHz HID Prox dual-technology combo — compatible stock exists because the chips are standard NXP MIFARE.

Quote HID FlexSmart MIFARE (1431/1441) cards View specs

Does American Key Cards make HID FlexSmart MIFARE (1431/1441) compatible cards?

Yes — American Key Cards supplies non-OEM HID FlexSmart MIFARE (1431/1441) compatible cards and key fobs (AKC MIFARE Classic compatible cards for FlexSmart-based systems — matched to how your system actually uses the chip (UID/CSN read vs sector data), verified from a working credential before ordering), encoded to your facility code and card-number range and ready to use on your existing HID readers. No hardware changes, no OEM dealer minimums, at a fraction of OEM pricing.

13.56 MHz (1441 combo: + 125 kHz)
Frequency: 13.56 MHz MIFARE Classic contactless smart card (1441 adds a 125 kHz HID Prox inlay)
Technology: 3
Bit formats: 2+
OEM part nos.: Yes
Cloneable

FlexSmart searches usually mean one of two things: a facility restocking MIFARE Classic badges its readers already enroll, or a migration site that needs the 1441's trick of carrying MIFARE and HID Prox in one card. American Key Cards supplies both — MIFARE Classic cards and fobs verified against how your system actually reads the chip, and dual-technology bodies for migration programs — by specification, with no dealer account. Not affiliated with HID Global.

HID FlexSmart MIFARE (1431/1441) specifications

Brand / OEM: HID Global / ASSA ABLOY
Technology: 13.56 MHz MIFARE Classic contactless smart card (1441 adds a 125 kHz HID Prox inlay)
Frequency: 13.56 MHz (1441 combo: + 125 kHz)
Chip: MIFARE Classic 1K / 4K
Bit formats: MIFARE Classic 1K — ISO/IEC 14443 Type A, 16 sectors, 4-byte NUID, MIFARE Classic 4K variants — 40 sectors, 1441 combo: 125 kHz HID Prox side in 26-bit H10301 and other HID formats
OEM part numbers: 1431 (MIFARE ISO card), 1441 (MIFARE + HID Prox combo)

Specifications reviewed June 2026

Our compatible HID FlexSmart MIFARE (1431/1441) credentials

American Key Cards manufactures non-OEM credentials engineered to work with your existing HID readers — no hardware changes, encoded to your facility code and card-number range.

AKC MIFARE Classic compatible cards for FlexSmart-based systems — matched to how your system actually uses the chip (UID/CSN read vs sector data), verified from a working credential before orderingProximity / ISO card

AKC MIFARE Classic key fob — same chip family in keyring formKey fob / tag

Full specifications, form factors and ordering FAQ: MIFARE Classic access cards & fobs

Can HID FlexSmart MIFARE (1431/1441) cards be cloned?

Yes — HID FlexSmart MIFARE (1431/1441) is an open format that can be reproduced from its facility code and card number. We don't copy individual cards on request, though — we manufacture new, correctly-encoded credentials for the systems you own or manage.

FlexSmart cards carry MIFARE Classic, whose CRYPTO1 cipher is cryptographically broken — sector keys are recoverable with published attacks, and UID-writable blank cards permit full duplication. Many FlexSmart deployments only read the card serial number (CSN/UID), which carries no cryptographic protection at all. The 125 kHz HID Prox side of the 1441 combo is unencrypted like any legacy prox credential. For new secure deployments, MIFARE DESFire EV3 is the appropriate upgrade path.

Where HID FlexSmart MIFARE (1431/1441) is used

Offices and facilities with 13.56 MHz readers enrolled on MIFARE Classic FlexSmart stock
Migration sites running the 1441 combo so one badge opens both old prox doors and new smart-card doors
Campus and multi-use deployments where the MIFARE sectors also drive vending or print release
Replacement stock for systems that enroll cards by MIFARE serial number (CSN)

Compatible readers

Any ISO/IEC 14443 Type A MIFARE Classic readerHID multiCLASS SE readers reading MIFARE CSN125 kHz HID Prox readers (the 1441 combo's prox side)

Related formats

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MIFARE

MIFARE Classic 1K

MIFARE Classic 1K is the world's most-deployed contactless smart card format, running at 13.56 MHz with 1 KB of CRYPTO1-protected memory across 16 sectors — widely used in legacy access control and hotel lock systems but known to be cloneable.

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MIFARE

MIFARE Classic 4K

MIFARE Classic 4K expands on the 1K format with 4,096 bytes across 40 sectors for multi-application campus and transit use, but shares the same broken CRYPTO1 cipher that makes all MIFARE Classic cards cloneable with off-the-shelf tools.

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HID

HID Prox H10301 (Standard 26-Bit)

The HID H10301 26-bit format is the most widely deployed proximity card format in North America, used on millions of doors across commercial and residential buildings.

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HID FlexSmart MIFARE (1431/1441) — FAQ

What is the HID FlexSmart line?

FlexSmart is HID's MIFARE-based card family: the 1431 is a printable ISO card carrying a MIFARE Classic chip, and the 1441 adds a 125 kHz HID Prox inlay in the same body so one badge works on both smart-card and legacy prox readers. The chips inside are standard NXP MIFARE Classic, which is why compatible stock exists.

Can an existing FlexSmart card be duplicated?

It depends on how your system uses the chip. If readers only check the MIFARE serial number (very common), compatible replacements are straightforward. If your system wrote data to encrypted sectors, MIFARE Classic's broken CRYPTO1 cipher makes duplication technically possible — but the honest route is enrolling fresh cards in your own software, which we supply blank or pre-serialized.

What is the difference between the 1431 and the 1441?

The 1431 is MIFARE-only — one 13.56 MHz chip. The 1441 is a dual-technology card: the same MIFARE chip plus a separate 125 kHz HID Prox antenna, used during migrations so a single badge opens doors on both the old prox system and the new smart-card system.

What should I send you to get matching cards?

The reader model and, ideally, a working credential. From those we confirm whether your system reads the MIFARE serial number or sector data, whether the prox side of a 1441 is actually in use, and which format and facility code it carries — then quote stock that enrolls cleanly.