MIFARE Classic 1K vs MIFARE Classic 4K
MIFARE Classic 1K offers 1024 bytes memory with Crypto-1 (broken) security, making it ideal for legacy transit cards, access control (legacy systems). MIFARE Classic 4K provides 4096 bytes with Crypto-1 (broken) security, suited for legacy transit with stored value, multi-application cards.
MIFARE Classic 1K
MIFARE Classic 4K
MIFARE Classic 1K vs MIFARE Classic 4K
Both MIFARE Classic variants share the same NXP-proprietary Crypto-1Crypto-1SecurityBroken proprietary cipher in MIFARE Classic (reverse-engineered 2008)Click to view → cipher and the same ISO 14443ISO 14443Standards & ProtocolsStandard for contactless smart cards at 13.56 MHz (Types A and B)Click to view →-3A air interface. The only meaningful difference is memory size. Yet that single dimension matters when choosing which card to deploy across a legacy access control or transit network.
Overview
MIFARE Classic 1K provides 1,024 bytes of user memory organized into 16 sectors of 4 blocks each. Each block is 16 bytes. Three blocks per sector are available for data; the fourth (Sector Trailer) stores two 48-bit keys (Key A and Key B) plus access condition bits. This gives 752 bytes of usable data space.
MIFARE Classic 4K provides 4,096 bytes total, organized as 32 sectors of 4 blocks plus 8 larger sectors of 16 blocks. Usable data capacity reaches approximately 3,440 bytes. Both chips are NFC-A (ISO 14443-3A Type A), operating at 13.56 MHz with a 4-byte or 7-byte UID.
Both chips use the Crypto-1 stream cipher, which was fully reverse-engineered in 2008. Multiple practical attacks — Darkside, Nested, Hardnested — allow card cloning and key recovery in seconds to minutes using commodity hardware. Neither chip is suitable for any new security-sensitive deployment.
Key Differences
- Memory: 1K offers 1,024 bytes (752 usable); 4K offers 4,096 bytes (~3,440 usable).
- Sector layout: 1K uses 16 uniform sectors. 4K uses 32 small sectors plus 8 large 16-block sectors for bulk data storage.
- Cost: Classic 4K cards carry a small premium (~10–20%) over Classic 1K at volume.
- Use case fit: 1K is sufficient for a single application (one transit balance, one access privilege). 4K supports multiple simultaneous applications or richer stored-value records.
- Security: Identical — Crypto-1 is broken on both. Neither offers any security advantage over the other.
Technical Comparison
| Parameter | MIFARE Classic 1K | MIFARE Classic 4K |
|---|---|---|
| Memory | 1,024 bytes | 4,096 bytes |
| Usable data | ~752 bytes | ~3,440 bytes |
| Sectors | 16 × 4 blocks | 32 × 4 blocks + 8 × 16 blocks |
| Block size | 16 bytes | 16 bytes |
| Security | Crypto-1 (broken) | Crypto-1 (broken) |
| UID | 4-byte or 7-byte | 4-byte or 7-byte |
| Air interface | ISO 14443-3A (NFC-A) | ISO 14443-3A (NFC-A) |
| Data rate | 106 kbps | 106 kbps |
| Read range | 0–10 cm | 0–10 cm |
| Operating frequencyOperating frequencyStandards & Protocols13.56 MHz ISM band frequency used by all NFC communicationsClick to view → | 13.56 MHz | 13.56 MHz |
| NFC ForumNFC ForumFundamentalsIndustry body developing NFC standards, specifications, and certifications since 2004Click to view → Tag Type | Not defined (proprietary) | Not defined (proprietary) |
| Typical card cost (volume) | $0.10–$0.25 | $0.15–$0.35 |
Use Cases
Where MIFARE Classic 1K Is Used
Classic 1K covers the overwhelming majority of MIFARE Classic deployments. One application sector is sufficient for a basic transit e-purse, a parking access token, or a single-door access privilege. Most legacy physical access control systems (HID compatible readers pre-2010, early Oyster readers) issued 1K cards.
- Legacy building access control (still operational, not being expanded)
- Dormant transit systems not yet migrated to DESFire
- Loyalty card programs on legacy infrastructure
- Replacement issuance for existing 1K cardholder populations
Where MIFARE Classic 4K Is Used
Classic 4K was chosen when a single card needed to host multiple applications — a transit e-purse alongside a canteen balance, for example — or when a loyalty program required a larger transaction history stored on-card. Today its primary use is in replacement issuance for deployed 4K populations.
- Multi-application legacy campus cards
- Transit cards with on-card transaction logs
- Stored-value parking or laundry systems needing more balance history
- Replacement stock for existing 4K cardholder deployments
Verdict
For any new deployment, neither chip should be chosen — MIFARE DESFire EV3 or NTAG 424 DNA provide genuine AES-128 security at comparable price points. Between the two Classic variants, choose Classic 1K for single-application replacements (lower cost, universal compatibility) and Classic 4K when existing infrastructure specifically encodes data into 4K's extended sector layout. The security posture is identical: both are cryptographically broken.
Rekomendasi
Choose MIFARE Classic 1K when you need massive installed base, widely available; choose MIFARE Classic 4K when you need largest Classic with 4 KB memory.