16. Appendix

16.1. Additional Resources

Got questions? Need more information? Want to contribute? There are a variety of other resources where you can find out more:

16.2. Keyboard mapping table

Shortcuts let you work more efficiently. This table lists the default keyboard shortcuts for accessing Mixxx with an English keyboard layout. Depending on your language settings the defaults may be different.

Function Deck 1 Deck 2 Master
Crossfade Left     G
Crossfade Right     H
Small Crossfade Left     Shift + G
Small Crossfade Right     Shift + H
Activate/Disable Effects Unit 5 0  
Headphone Cue (Pre-fader listen) T Y  
Bass Kill B N  
Load selected track to deck Shift + left Shift + right  
Unload track from deck Alt + Shift + left Alt + Shift + right  
Playback D L  
Seek Backwards A J  
Reverse Playback Shift + A Shift + J  
Seek Forwards S K  
Tempo Adjust Down F1 F5  
Tempo Adjust Up F2 F6  
Small Tempo Adjust Down Shift + F1 Shift + F5  
Small Tempo Adjust Up Shift + F2 Shift + F6  
Temporary Tempo Adjust Down F3 F7  
Temporary Tempo Adjust Up F4 F8  
Small Temporary Tempo Adjust Down Shift + F3 Shift + F7  
Small Temporary Tempo Adjust Up Shift + F4 Shift + F8  
Tempo (BPM) Sync 1 6  
BPM Tap Tempo Adjust Shift + ! Shift + ^  
Cue and Loop
Set Cuepoint Shift + D Shift + L  
Cue F ;  
Cue Go-to-and-stop Shift + F Shift + :  
Activate 4 Beat Loop Q U  
Halve Beat Loop Size W I  
Double Beat Loop Size E O  
Set Loop In Point 2 7  
Set Loop Out Point (Activates Loop) 3 8  
Toggle Loop On/Off 4 9  
Set Hot cue 1 Z M  
Set Hot cue 2 X ,  
Set Hot cue 3 C .  
Set Hot cue 4 V /  
Clear Hot cue 1 Shift + Z Shift + M  
Clear Hot cue 2 Shift + X Shift + <  
Clear Hot cue 3 Shift + C Shift + >  
Clear Hot cue 4 Shift + V Shift + ?  
Microphone Talkover     `
Auto DJ
Shuffle Auto DJ playlist     Shift + F9
Skip next track in Auto DJ     Shift + F10
Fade to next track in Auto DJ     Shift + F11
Toggle Auto DJ on/Off     Shift + F12
Preview Deck
Load Selected Track And Play     Alt + Return
Start/Stop     Return
Seek Backwards     Alt + Left
Seek Forwards     Alt + Right
Vinyl Control
Passthrough Ctrl + J Ctrl + K  
Vinylcontrol Mode Ctrl + Shift + Y Ctrl + Shift + U  
Vinylcontrol Cueing Ctrl + Alt+ Y Ctrl + Alt + U  
Single Deck Toggle / Swap Decks Ctrl + T Ctrl + T  
Search bar
Focus Ctrl + F
Clear input Ctrl + Back
Exit search and leave focus ESC
Select all files in current list Ctrl + A
Select group of files in current list Click first item, hold Shift key, click last item

See also

Mixxx allows you to customize the keyboard shortcuts. For more information, and to download a keyboard mapping image, go to Using a Keyboard.

16.3. Application shortcuts

Use these shortcuts to access features available in the menu on top of the application window.

Function Key
File menu
Load Track to Deck 1 Ctrl + O
Load Track to Deck 2 Ctrl + Shift + O
Library menu
Add new Playlist Ctrl + N
Add new Crate Ctrl + Shift + N
View menu
Show Samplers Ctrl + 1
Show Microphone Section Ctrl + 2
Show Vinyl Control Section Ctrl + 3
Show Preview Deck Ctrl + 4
Show Effect Rack Ctrl + 5
Show Cover Art Ctrl + 6
Maximize Library Space
Full Screen (Windows & Linux) F11
Full Screen (macOS) Shift + Command + F
Options menu
Enable Vinyl Control 1 Ctrl + T
Enable Vinyl Control 2 Ctrl + Y
Enable Vinyl Control 3 Ctrl + U
Enable Vinyl Control 4 Ctrl + I
Enable Live Broadcasting Ctrl + L
Record Mix Ctrl + R
Enable Keyboard Shortcuts Ctrl + `
Open Preferences (Windows & Linux) Ctrl + P
Open Preferences (macOS) Ctrl + ,
Exit Mixxx Ctrl + Q
Developer menu
Reload skin Ctrl + Shift + R
Developer Tools Ctrl + Shift + T
Stats: Base Bucket Ctrl + Shift + B
Stats: Experiment Bucket Ctrl + Shift + E
Debugger Enabled Ctrl + Shift + D


The Ctrl key on Windows & Linux is equivalent to the Command key on macOS. The Alt key on Windows & Linux is equivalent to the Option key on macOS. Application shortcuts are not customizable.


The Developer menu is available if Mixxx is started using the Command line options.

16.4. Command line options

Mixxx is designed to be as user-friendly as possible. As such, its command line options are only useful for development or debugging, as they make these tasks easier. Command line options are case-sensitive.

    New in version 2.1.0:
  • --debugAssertBreak option

  • --logLevel option

  • --logFlushLevel option

    Changed in version 2.1.0:
  • --controllerDebug option also prints outgoing MIDI messages

Option Description
[FILE] Load the specified music file(s) at start-up. Each file you specify will be loaded into the next virtual deck. For a list of supported file types, go to Changing music directories
–resourcePath PATH Top-level directory where Mixxx should look for its resource files such as MIDI mappings, overriding the default installation location.
–pluginPath PATH Top-level directory where Mixxx should look for sound source plugins in addition to default locations.
–settingsPath PATH Top-level directory where Mixxx should look for user settings files such as the library database and preferences configuration file.
–controllerDebug Causes Mixxx to display/log all controller data it sends and receives, and script functions it loads.
–developer Enables developer-mode. Includes extra log info, stats on performance, a Developer tools menu, extra developer skins, and provides useful information for skin writers in widget tooltips and logs .

Disables risky things at start up. This should help troubleshoot crashes at startup or if Mixxx won’t boot.

  • Automatically loads empty waveforms
  • Disables spinning vinyl widgets
  • Disables synchronization polling
  • Doesn’t open controllers by default
–locale LOCALE Use a custom locale for loading translations (e.g fr)
-f, –fullScreen Starts Mixxx in full-screen mode
–logLevel LEVEL

Sets the verbosity of command line logging

  • critical - Critical/Fatal only
  • warning - Above + Warnings
  • info - Above + Informational messages
  • debug - Above + Debug/Developer messages
  • trace - Above + Profiling messages
–logFlushLevel LEVEL Sets the the logging level at which the log buffer is flushed to mixxx.log. LEVEL is one of the values defined at --logLevel above.
–debugAssertBreak Breaks (SIGINT) Mixxx, if a DEBUG_ASSERT evaluates to false. Under a debugger you can continue afterwards. This will also avoid to switch the MIXXX_DEBUG_ASSERTIONS_FATAL flag which leads to a time consuming full rebuild. Now the MIXXX_DEBUG_ASSERTIONS_FATAL is only respected if --debugAssertBreak is not passed.
-h, –help Display this help message and exit

16.5. Developer tools

To start Mixxx in Developer mode from a custom resource directory with MIDI and HID logging enabled, type the following line into the terminal and hit return:

./mixxx --controllerDebug --developer --resourcePath res

16.5.1. Experiment modes for rapid development and testing

  • Adds a static Experiment class with a tri-state mode flag that indicates whether the experiment mode is OFF, BASE, or EXPERIMENT.
  • Adds Developer ‣ Stats:Experiment Bucket and Developer ‣ Stats:Base Bucket. Each one toggles between OFF and BASE/EXPERIMENT so you can choose exactly what time spans you would like to collect in your base and experiment buckets.
  • Updates StatsManager to segment collected stats into a base and experiment bucket. This allows you to quickly measure the difference a code change has on relevant counters / timers within the same execution of Mixxx.

This is useful for quickly enabling and disabling a code change without a re-compile/re-run cycle to get an anecdotal sense of how it “feels” as well as a quantified sense of how it differs in terms of stats Mixxx collects.

All stats collected via the usual Counter/Timer/ScopedTimer/etc. tools are segmented into a BASE STATS and EXPERIMENT STATS section printed to the log on exit.

16.6. Version History

v2.1.0 (2018-04-15)

  • Graphical interface scales for high resolution screens
  • Overhauled Deere and LateNight skins
  • New Tango skin
  • Resizable waveforms
  • Effects are synchronized to the tempo
  • Effects are processed post-fader and post-crossfader and can be previewed in headphones
  • One metaknob per effect with customizable parameter control for intuitive use of effect chains
  • Nine new effects: Autopan, Biquad Equalizer, Biquad Full Kill Equalizer, Loudness Contour, Metronome, Parametric Equalizer, Phaser, Stereo Balance, Tremolo
  • Loaded effects and their parameters are saved and restored when Mixxx restarts
  • More transparent sounding equalizers (Biquad Equalizer and Biquad Full Kill Equalizer)
  • Improved scratching sounds with jog wheels, vinyl control, and dragging waveforms with the mouse
  • Simplified looping and beatjump controls
  • Configurable rows of 8 samplers with up to 8 rows available for a total of 64 samplers
  • Files loaded to samplers are reloaded when Mixxx restarts
  • Improved volume normalization algorithm (EBU-R 128)
  • Filter library table by crates
  • Sort musical keys in library table by circle of fifths
  • Write metadata tags back to audio files
  • New JavaScript library for controller mapping
  • Configure multiple Internet broadcasting stations and use multiple stations at the same time
  • Broadcast and record microphones with direct monitoring and latency compensation
  • Broadcast and record from an external mixer
  • Booth output with independent gain knob for using sound cards with 6 output channels without an external mixer
  • Prevent screensaver from starting while Mixxx is running
  • CUP (Cue And Play) cue button mode
  • Time remaining and time elapsed now take into account the tempo fader
  • Clicking cover art now shows it full size in a separate window

For a full list of new features and bugfixes, go to: https://launchpad.net/mixxx/2.1.

v2.0.0 (2015-12-31)

  • 4 Decks with Master Sync
  • New Effects Framework with 4 Effect Units and 5 Built-in Effects: * Flanger, Bit Crusher, Reverb, Echo, Filter * More to come!
  • Configurable, Resizeable User Interface with 3 Brand New Skins
  • Cover Art Display
  • Music Key Detection and Shifting
  • Vinyl Audio Pass-Through
  • 4 Microphone inputs and 4 Auxiliary inputs
  • MIDI Mapping GUI and Improved Learning Wizard
  • MusicBrainz metadata fetching
  • RGB Musical Waveforms
  • Hundreds of Bug Fixes and Improvements
  • New Pitch-Independent Algorithm for Better-Sounding Key-lock

For a full list of new features and bugfixes, go to: https://launchpad.net/mixxx/2.0.

See also

For an overview of previous versions, take a look at the timeline.