Find out your Flarm-ID

Often pilots want to Opt-In or Opt-Out but they don't know where to get their Flarm-ID(RadioID) or ICAO24 Address from.

This page should help to find out your Flarm-ID or ICAO24 Address.


Classic Flarm

To be clear the Radio-ID is not the Serial number of the Unit.
The ClassicFlarm Serial number can be found on the case. Starting with the Hardwareversion like F5… F6… F7…followed by 4 numbers.

Sticker at the Bottom of Case

If your Flarm is an IGC-Valid-Logger you might have a chance that there is a sticker at the bottom of your device telling you what the Flarm-ID is.


(small Sticker at the Top ID= DDA300)

Download IGC Files and CSV File to Micro-SD-Card

If your Flarm is equipped with a Micro-SD-Card slot then you can insert a card and startup your Flarm to download the IGC Files. Together with the downloaded IGC files there will be a flarmdev.csv file.
Open it in any text editor (or Excel) and find an entry for each Downloadprocedure.
Search for the last line and look at ID=


Readout from IGC File

Download some IGC Files from your Flarm. Use Micro-SD-Card or XCSoar (connected via cable or Bluetooth) or just download them from the OLC-Server.
If you open the IGC-File in a text editor you can scroll down a bit till you find the Line starting with LFLA and ID


Upload an IGC File to RangeAnalyzer

IGC can also be uploaded to the RangeAnalyzer from Navigate to Support —> Tools & Software —> FLARM Range Analyzer (
select your IGCf file and click on "UPLOAD & ANALYZE IGC FILE" a new page will be loaded showing you the result of your FLARM Reception Range, where you should be able to see your device's FLARM-ID.


Readout via FlarmTool

You can also connect your Flarm with a serial cable to a computer and run the FlarmTool which comes with the Softwareupdate from Once Flarm is connected, you should be able to see RadioID on the main screen.


a IGC-Valid Flarm


non IGC-Valid Flarm (no IGC-Number)

OGN-Viewer app

if the Flarm is not setup for NOTRACK and it is in an Area with coverage you can also use the OGN-Viewer App. Turn on your device, run the application, then select your placemark. The popup will show your Flarm-ID

Other Flarm devices


needs to be written


needs to be written


needs to be written

ICAO24 Address

In Germany you need to pay a fee to get your own ICAO24 Address.


If your aircraft is registered or already got an ICAO24-Address it is possible to look up in the Airframes Database.
Type in your registration. You will find the ICAO24 Ccde and the Flarm-ID (if it was registered there)

Gatwick Aviation Society

At this website you can search for your registration and it will show the ICAO24 address at the Mode-S code field

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