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MMSI Lookup and IMO Number Check

Type a 9-digit MMSI to see which country issued it and what kind of station it is, or a 7-digit IMO number to check that it is valid. Free and instant.

Enter an MMSI or IMO number

MMSI
247123456
Station type
Ship station
MID
247
Flag
Italy
ITU region
Europe

How to Look Up an MMSI

Three steps from a number to what it means

01

Enter the number

Type or paste the MMSI (9 digits) or the IMO number (7 digits, with or without "IMO" in front).

02

Read the answer

An MMSI shows its station type, its MID and the flag country. An IMO number shows whether its check digit is right.

03

Find the ship

Open the number in Primo Nautic to see where the ship is now, where it is going and when it arrives.

What an MMSI Tells You

Read straight from the number under ITU-R M.585

Flag country

The Maritime Identification Digits (MID) in an MMSI name the country that issued it, which is the ship's flag state.

Station type

The format tells a ship apart from a coast station, a buoy or light, a SAR aircraft, a handheld radio or a distress beacon.

IMO check digit

The last digit of an IMO number is a checksum of the first six, so a mistyped number shows up at once.

Private and instant

The lookup runs in your browser. The number is never sent anywhere, and there is no account or limit.

Who Uses an MMSI Lookup

Who it is for and what they use it for

Ship spotters and AIS users

Find out where an unknown AIS target is registered, and whether it is a ship, a buoy or a shore station.

Shipping and chartering

Check an IMO number from a fixture, a bill of lading or a vetting form before it goes into a system.

Boat owners and radio operators

Confirm the country and format of an MMSI for a VHF radio, an AIS transponder or an EPIRB.

Frequently Asked
Questions

Everything you need to know about the MMSI Lookup.

A Maritime Mobile Service Identity is a 9-digit number that identifies a ship's radio station in AIS, DSC radio and distress beacons. It is issued by the flag state's telecom authority and changes when a ship changes flag.

For a ship, the first three digits are the Maritime Identification Digits (MID), assigned to each country by the ITU. 247 is Italy, 366 to 369 are the United States and 351 to 357 and 370 to 374 are Panama. Coast stations, buoys and beacons carry the MID further along, which this tool reads for you.

The IMO number is a 7-digit number given to a ship's hull, and it stays the same for the ship's whole life, whatever its name or flag. The MMSI belongs to the radio station and changes with the flag. Use the IMO number to identify a ship over time and the MMSI to find it in AIS.

Multiply the first six digits by 7, 6, 5, 4, 3 and 2, add the results, and the last digit of that sum must equal the seventh digit. For IMO 9074729: 9x7 + 0x6 + 7x5 + 4x4 + 7x3 + 2x2 = 139, which ends in 9.

No. It reads what the number itself says, with no database search. To see a ship's name, live position and arrival time, open it in the Primo Nautic app.

00 is a coast station and a single 0 a group of ships. 8 is a handheld VHF radio. 970, 972 and 974 are an AIS-SART, a man overboard device and an EPIRB. 98 is a craft working with a parent ship, such as a lifeboat, and 99 is an aid to navigation such as a buoy or a lighthouse.

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