Scroll to navigation


NAME dump1090-mutability - Mode-S decoder


dump1090-mutability --interactive
dump1090-mutability --ifile file


dump1090-mutability receives and decodes Mode S packets using the Realtek RTL2832 software defined radio interface. It provides the ability to decode multiple frame types as well as correct bit errors using the embedded 24-bit CRC. Results can be viewed using a text client, via the built- in HTTP server or forwarded off to other locations for collection.


The supported options are as follows:

Select RTL device (default: 0)
Set gain (default: max gain. Use -10 for auto-gain)
Enable the Automatic Gain Control (default: off)
Set frequency (default: 1090 Mhz)
Read data from file (use '-' for stdin)
Display received in a textual table, in real-time.
Max number of rows in interactive mode (default: 15)
Remove from list if idle for sec (default: 60)
Display flight table in RTL1090 format
Show only messages hex values

--net Enable networking

Enable decoding of SSR Modes 3/A & 3/C
TCP raw output in Beast binary format
Enable just networking, no RTL device or file used
HTTP server port (default: 8080)
TCP raw input listen port (default: 30001)
TCP raw output listen port (default: 30002)

--net-sbs-port port TCP BaseStation output listen port (default: 30003)

TCP Beast input listen port (default: 30004)
TCP Beast output listen port (default: 30005)
TCP raw output minimum size (default: 0)
TCP raw output memory flush rate (default: 0)
TCP heartbeat rate in seconds (default: 60; 0 to disable)
TCP buffer size 64Kb * (2^n) (default: n=0, 64Kb)
Reference/receiver latitude for surface posn (opt)
Reference/receiver longitude for surface posn (opt)
Enable single-bits error correction using CRC
Disable single-bits error correction using CRC
Disable messages with broken CRC (discouraged)
Enable phase enhancement
More CPU for more messages (two bits fixes, ...)
display raw messages in Beast ascii mode
With --ifile print stats at exit. No other output
Show only ICAO addresses (testing purposes)
Use metric units (meters, km/h, ...)
Strip IQ file removing samples level
Debug mode (verbose)
Disable output to stdout.
Set receiver error in parts per million (default 0)
Show help


The Debug mode is a visual help to improve the detection algorithm or to understand why the program is not working for a given input.

In this mode messages are displayed in an ASCII-art style graphical representation, where the individual magnitude bars sampled at 2MHz are displayed.

An index shows the sample number, where 0 is the sample where the first Mode S peak was found. Some additional background noise is also added before the first peak to provide some context.

Select frames to log using the following flags:

Log frames decoded with errors
Log frames decoded with zero errors
Log frames with bad CRC
Log frames with good CRC
Log frames with bad preamble
Log network debugging info
Log frames to frames.js, loadable by debug.html


Most people will either run this in interactive mode or as a daemon.

Interactive mode

dump1090-mutability --interactive
Daemon mode

dump1090-mutability --net --quiet &
You can also use dump1090-mutability as a network hub for multiple receivers by using

dump1090-mutability --net-only


Report bugs with the program to the project's github page <>


Dump1090 was originally written by Salvatore Sanfilippo <>. This version is now maintained by Oliver Jowett <>. This manpage was prepared for Debian by Matthew Ernisse <>.

17 August 2014