{
  "url": "https://proudtek.com/compare/em4100-vs-t5577/",
  "sourceUrl": "https://proudtek.com/compare/em4100-vs-t5577/",
  "title": "EM4100 vs T5577 — The Practical 125 kHz LF Chip Comparison for Access, Cloning, Hotel Retrofit and Migration",
  "description": "EM4100 and T5577 are the two chip families that dominate the 125 kHz low-frequency (LF) RFID world. EM4100 is read-only — it ships from EM...",
  "kind": "article",
  "imageUrl": "https://proudtek.com/landing-images/em4100-vs-t5577-hero.jpg",
  "imageAlt": "Tall stack of plain white PVC RFID cards on a white background",
  "imageGallery": [
    {
      "url": "https://proudtek.com/landing-images/em4100-vs-t5577-hero.jpg",
      "alt": "Tall stack of plain white PVC RFID cards on a white background"
    }
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    {
      "name": "EM4100 vs T5577 — The Practical 125 kHz LF Chip Comparison for Access, Cloning, Hotel Retrofit and Migration",
      "url": "https://proudtek.com/compare/em4100-vs-t5577/"
    }
  ],
  "summary": [
    "EM4100 and T5577 are the two chip families that dominate the 125 kHz low-frequency (LF) RFID world."
  ],
  "faq": [
    {
      "question": "Can I tell from looking at a card whether it is EM4100 or T5577?",
      "answer": "Not visually — both ship in the same standard 85 × 55 mm PVC body and the antenna geometry is identical. Distinguishing them requires either a tool that reads the chip ID (Proxmark3 will report the chip model on detection) or the per-SKU markings the manufacturer applies. Proud Tek labels every box of cards with the chip family and protocol on the lot label so receiving teams can verify."
    },
    {
      "question": "Will a T5577 emulating EM4100 work on every EM4100 reader?",
      "answer": "On every commodity 125 kHz reader, yes. The handful of high-end HID ICLASS SE / multiCLASS readers that perform timing-side-channel rejection of cloned credentials are the exception, and even those can be bypassed by the latest Proxmark3 firmware revisions. Treat T5577 emulation as functionally equivalent for the 95% of reader fleets in commercial use."
    },
    {
      "question": "Can T5577 be password-protected to prevent cloning?",
      "answer": "Yes — T5577 supports a 32-bit password lock on the configuration block, which prevents re-writing the modulator config or the data without the password. In practice this is rarely deployed because (a) it does not prevent reading the credential and creating an emulation, and (b) password management adds operational overhead. Password protection is more common in test / lab / pentest fleets than in commodity issuance."
    },
    {
      "question": "Is there a 'secure' 125 kHz chip family that defeats commodity cloning?",
      "answer": "Not at commodity price points. HITAG 1 / HITAG 2 / HITAG S add some authentication, but the chips and readers are an order of magnitude more expensive than EM4100/T5577 and HITAG 2 has known vulnerabilities. The practical secure-credential path is to migrate to 13.56 MHz (MIFARE Plus EV2 SL3 or MIFARE DESFire EV3) where AES-128 mutual authentication eliminates the commodity cloning surface entirely. See the linked /compare/125khz-vs-13.56mhz-rfid/ page for the full migration analysis."
    },
    {
      "question": "What MOQ does Proud Tek require for either chip?",
      "answer": "EM4100 and T5577 cards are stocked in standard PVC formats and Proud Tek can ship from 1,000 units. The unit-cost ladder flattens above 50,000 units; below 50,000 units the price ladder steepens because lamination tooling amortises across fewer units. Keyfob form factors carry a higher tooling minimum (typically 5,000 units) but the chip cost is the same."
    },
    {
      "question": "Does either chip work with iPhone NFC reading?",
      "answer": "No. Both EM4100 and T5577 are 125 kHz LF chips. iPhone (and every NFC-enabled smartphone) reads 13.56 MHz HF chips per the NFC Forum specification — not 125 kHz. If smartphone compatibility is a requirement, the chip family must move to 13.56 MHz (MIFARE / NTAG / FeliCa / ICODE)."
    }
  ],
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    {
      "label": "Best for",
      "value": "EM4100 vs T5577 — The Practical 125 kHz LF Chip Comparison for Access, Cloning, Hotel Retrofit and Migration supports RFID and NFC evaluation, comparison, and sourcing decisions."
    },
    {
      "label": "Compare first",
      "value": "Compare EM4100 vs T5577 — The Practical 125 kHz LF Chip Comparison for Access, Cloning, Hotel Retrofit and Migration against reader compatibility, chip family, material, and deployment environment."
    },
    {
      "label": "What to confirm",
      "value": "Confirm target application, compatibility requirements, customization needs, quantity, and sample expectations before quoting EM4100 vs T5577 — The Practical 125 kHz LF Chip Comparison for Access, Cloning, Hotel Retrofit and Migration."
    }
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  "machineJsonUrl": "https://proudtek.com/machine/compare/em4100-vs-t5577.json",
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  "author": {
    "name": "Proud Tek Editorial Team",
    "title": "RFID & NFC Technical Content Team",
    "expertise": [
      "RFID manufacturing",
      "NFC technology",
      "Access control systems",
      "Smart card engineering"
    ]
  },
  "publisher": "Proud Tek Co., Limited",
  "datePublished": "2026-05-13",
  "dateModified": "2026-06-10T01:00:47Z",
  "lastReviewedDate": "2026-06-10T01:00:47Z",
  "credentials": [
    "ISO 9001:2015",
    "ISO 14001:2015",
    "RoHS Compliant",
    "CE Marking",
    "REACH Compliant"
  ],
  "generatedAt": "2026-03-16T01:42:30.697Z"
}