Comprehensive technical knowledge base covering 12 GSMA eSIM specifications. 84+ articles on Remote SIM Provisioning — SGP.02, SGP.22, SGP.32, SGP.41, SGP.29, SGP.23, SGP.25, SGP.26 and more.
You look at an international phone number: +1-555-123-4567. Even without knowing whose number it is, you can decode it: +1 means North America, 555 is the area code, and the rest is the local number. The EID works the same way: those 32 digits aren’t random. They’re a carefully structured code that tells a story!
Every EID is exactly 32 digits long, built from three pieces:
┌──────────────────────────────────────────────────────────┐
│ EID: 32 Digits Total │
├──────────────────────┬─────────────────┬─────────────────┤
│ EIN (N digits) │ ESIN (30-N) │ Check (2) │
│ Who made the chip? │ Which chip? │ Is this valid? │
└──────────────────────┴─────────────────┴─────────────────┘
| Part | Name | What It Tells You |
|---|---|---|
| EIN | EUM Identification Number | The delegation chain: who authorised this chip’s name |
| ESIN | EUM Specific Identification Number | Which individual chip this is (like a serial number within a batch) |
| Check | Check Digits (2 digits) | A mathematical fingerprint that proves the EID is genuine |
The EIN can be different lengths (N digits). The ESIN fills whatever’s left up to position 30. The last 2 digits are always the check. So: EIN + ESIN = always 30 digits + 2 check digits = 32 total.
The EIN isn’t just a single number: it’s built by chaining together ERHI (EID Range Holder Identifier) values, one from each level of authority:
EIN = ERHI1 + ERHI2 + ERHI3 + ... + ERHIx
│ │ │ │
│ │ │ └─ Assigned to the chip maker (EUM)
│ │ └─ Assigned by a device maker or national authority
│ └─ Assigned by a national authority or device maker
└─ Assigned by the GSMA (the head librarian!)
Three levels (GSMA → National Authority → Device Maker → Chip Maker):
GSMA assigns "12" → National Authority
→ National Authority assigns "345" → Device Maker
→ Device Maker assigns "67" → Chip Maker
→ EIN = "1234567" (N=7)
Two levels (GSMA → Device Maker → Chip Maker):
GSMA assigns "98" → Device Maker
→ Device Maker assigns "76" → Chip Maker
→ EIN = "9876" (N=4)
The chain can be as short or as long as needed: whatever fits the real-world supply chain!
Here’s the coolest part. The last 2 digits let anyone verify an EID with simple math using the MOD 97-10 algorithm: the same one banks use to validate IBAN numbers!
Let’s check this EID: 12345000000000000000000000000133
12345000000000000000000000000133 ÷ 97 = ???
Remainder = 1 ✅ VALID!
If someone accidentally typed 12345000000000000000000000000134:
Remainder ≠ 1 ❌ INVALID! (someone made a typo!)
This check catches 100% of single-digit typos and 100% of swapped digits. It’s incredibly reliable!
| Property | EID (SGP.29) | ICCID (Old SIM) | IMEI (Phone ID) |
|---|---|---|---|
| Length | 32 digits | Up to 20 digits | 15 digits |
| Purpose | Identify eSIM chip | Identify SIM account | Identify phone device |
| Starts with | Anything except “89” | Always “89” | Type code (8 digits) |
| Check method | MOD 97-10 (bank-grade!) | Luhn MOD 10 | Luhn MOD 10 |
| Who manages it | GSMA | National authorities | GSMA / TIA |
The big difference? EIDs never start with “89” : that prefix is reserved for old-style SIM card identifiers. This prevents any possible mix-up between the two systems!
The MOD 97-10 check digit algorithm is the exact same one used for IBANs (International Bank Account Numbers). Your eSIM chip’s identity is verified with banking-grade mathematics. If a single digit is wrong anywhere in the 32-digit EID, the check will catch it every single time!
Kid-friendly version of GSMA SGP.29 v1.1: EID Format, Section 10