What Is an IMEI Number? A Plain-English Guide
The 15-digit fingerprint every phone carries — what it is, where to find it, and why it matters.
IMEI stands for International Mobile Equipment Identity. It is a 15-digit number assigned to every cellular device at the factory, and unlike a phone number or a SIM, it belongs to the hardware itself. Swap SIMs, change owners, cross borders — the IMEI stays put.
The number is not random. Its opening digits form the Type Allocation Code, which identifies the make and model, which is how a lookup can name your exact device before it checks anything else. The remaining digits identify the individual unit, with a final check digit that guards against typos.
To see yours, dial *#06# on the keypad and it appears instantly. You will also find it in Settings, printed on the original box, and etched on the SIM tray of many phones. Dual-SIM devices carry two IMEIs, one per radio.
Because the IMEI is unique and permanent, networks and databases use it as the anchor for everything: whether a phone is locked to a carrier, whether it has been reported lost or stolen, and whether its warranty is still active. That is why a single number can unlock a phone's entire history.
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See device, blacklist and lock status in seconds — no signup. Dial *#06# on the phone to display its IMEI — or scan a photo or screenshot of that screen, or of the barcode on the phone's box or SIM tray.
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Common questions
How many digits is an IMEI?
A standard IMEI is 15 digits. You may occasionally see a 16- or 17-digit IMEISV, which adds a software-version suffix.
What does an IMEI number look like, and what do its digits mean?
It is always a 15-digit number — for example 351234567890124 (an illustrative sample, not a real phone). The digits are not random; they follow a fixed structure. The first 8 (here 35123456) are the Type Allocation Code, which identifies the make and model, so a lookup can name your device before it checks anything else. The next 6 (789012) are the serial number that makes this individual unit unique within that model. The final digit (4) is a check digit calculated from the other fourteen, so software can catch a single mistyped number. A longer 16-digit variant is the IMEISV, which replaces that check digit with a two-digit software-version code. If dialling *#06# returns anything other than a clean 15-digit number — a blank, all zeros or "null" — that is a red flag, not a formatting quirk.
What does it mean if my IMEI shows as 0, blank, or "null"?
It is a warning sign. A genuine IMEI is always a 15-digit number, so if *#06# or Settings returns 0, all zeros, "null", "unknown", or nothing at all, the phone's IMEI has been erased, corrupted, or never written correctly — often after a botched software flash, a grey-market repair, or a deliberate attempt to hide a blacklisted device's real identity. A handset with a missing or invalid IMEI usually cannot register on a cellular network at all: no calls, texts or mobile data, and some carriers reject it outright. If a used phone you are looking at shows a blank or zero IMEI, treat it as a serious red flag — do not pay until a valid 15-digit number appears that matches the original box and returns a clean lookup.
Is the IMEI the same as a serial number?
No. The serial number is the manufacturer's own tracking code; the IMEI is a globally standardized cellular identifier used by networks worldwide.
Can two phones share an IMEI?
They should not. A duplicate usually signals a cloned or tampered device, which is a serious red flag when buying used.
Does changing my SIM change the IMEI?
No. The IMEI is tied to the hardware, not the SIM or phone number, so it never changes when you switch SIMs.