Command Line Arguments

Blender 2.81 Usage: blender [args …] [file] [args …]

Render Options

-b, --background
Run in background (often used for UI-less rendering).
-a, --render-anim
Render frames from start to end (inclusive).
-S, --scene <name>
Set the active scene <name> for rendering.
-f, --render-frame <frame>

Render frame <frame> and save it.

  • +<frame> start frame relative, -<frame> end frame relative.
  • A comma separated list of frames can also be used (no spaces).
  • A range of frames can be expressed using .. separator between the first and last frames (inclusive).
-s, --frame-start <frame>
Set start to frame <frame>, supports +/- for relative frames too.
-e, --frame-end <frame>
Set end to frame <frame>, supports +/- for relative frames too.
-j, --frame-jump <frames>
Set number of frames to step forward after each rendered frame.
-o, --render-output <path>

Set the render path and file name. Use // at the start of the path to render relative to the blend-file.

The # characters are replaced by the frame number, and used to define zero padding.

  • animation_##_test.png becomes animation_01_test.png
  • test-######.png becomes test-000001.png

When the filename does not contain #, The suffix #### is added to the filename.

The frame number will be added at the end of the filename, eg:

blender -b animation.blend -o //render_ -F PNG -x 1 -a

//render_ becomes //render_####, writing frames as //render_0001.png

-E, --engine <engine>
Specify the render engine. Use -E help to list available engines.
-t, --threads <threads>
Use amount of <threads> for rendering and other operations [1-64], 0 for systems processor count.

Format Options

-F, --render-format <format>

Set the render format. Valid options are: TGA RAWTGA JPEG IRIS IRIZ AVIRAW AVIJPEG PNG BMP

Formats that can be compiled into Blender, not available on all systems: HDR TIFF OPEN_EXR OPEN_EXR_MULTILAYER MPEG CINEON DPX DDS JP2

-x, --use-extension <bool>
Set option to add the file extension to the end of the file.

Animation Playback Options

-a <options> <file(s)>

Instead of showing Blender’s user interface, this runs Blender as an animation player, to view movies and image sequences rendered in Blender (ignored if -b is set).

Playback Arguments:

-p <sx> <sy>
Open with lower left corner at <sx>, <sy>.
-m
Read from disk (Do not buffer).
-f <fps> <fps-base>
Specify FPS to start with.
-j <frame>
Set frame step to <frame>.
-s <frame>
Play from <frame>.
-e <frame>
Play until <frame>.

Window Options

-w, --window-border
Force opening with borders.
-W, --window-fullscreen
Force opening in fullscreen mode.
-p, --window-geometry <sx> <sy> <w> <h>
Open with lower left corner at <sx>, <sy> and width and height as <w>, <h>.
-M, --window-maximized
Force opening maximized.
-con, --start-console
Start with the console window open (ignored if -b is set), (Windows only).
--no-native-pixels
Do not use native pixel size, for high resolution displays (MacBook Retina).
--no-window-focus
Open behind other windows and without taking focus.

Python Options

-y, --enable-autoexec
Enable automatic Python script execution (default).
-Y, --disable-autoexec
Disable automatic Python script execution (pydrivers & startup scripts).
-P, --python <filename>
Run the given Python script file.
--python-text <name>
Run the given Python script text block.
--python-expr <expression>
Run the given expression as a Python script.
--python-console
Run Blender with an interactive console.
--python-exit-code <code>
Set the exit-code in [0..255] to exit if a Python exception is raised (only for scripts executed from the command line), zero disables.
--addons <addon(s)>
Comma separated list of add-ons (no spaces).

Logging Options

--log <match>
Enable logging categories, taking a single comma separated argument. Multiple categories can be matched using a .* suffix, so --log "wm.*" logs every kind of window-manager message. Use „^“ prefix to ignore, so --log "*,^wm.operator.*" logs all except for wm.operators.* Use „*“ to log everything.
--log-level <level>
Set the logging verbosity level (higher for more details) defaults to 1, use -1 to log all levels.
--log-show-basename
Only show file name in output (not the leading path).
--log-show-backtrace
Show a back trace for each log message (debug builds only).
--log-show-timestamp
Show a timestamp for each log message in seconds since start.
--log-file <filename>
Set a file to output the log to.

Debug Options

-d, --debug

Turn debugging on.

  • Enables memory error detection
  • Disables mouse grab (to interact with a debugger in some cases)
  • Keeps Python’s sys.stdin rather than setting it to None
--debug-value <value>
Set debug value of <value> on startup.
--debug-events
Enable debug messages for the event system.
--debug-ffmpeg
Enable debug messages from FFmpeg library.
--debug-handlers
Enable debug messages for event handling.
--debug-libmv
Enable debug messages from libmv library.
--debug-cycles
Enable debug messages from Cycles.
--debug-memory
Enable fully guarded memory allocation and debugging.
--debug-jobs
Enable time profiling for background jobs.
--debug-python
Enable debug messages for Python.
--debug-depsgraph
Enable all debug messages from dependency graph.
--debug-depsgraph-eval
Enable debug messages from dependency graph related on evaluation.
--debug-depsgraph-build
Enable debug messages from dependency graph related on graph construction.
--debug-depsgraph-tag
Enable debug messages from dependency graph related on tagging.
--debug-depsgraph-no-threads
Switch dependency graph to a single threaded evaluation.
--debug-depsgraph-time
Enable debug messages from dependency graph related on timing.
--debug-depsgraph-pretty
Enable colors for dependency graph debug messages.
--debug-gpu
Enable gpu debug context and information for OpenGL 4.3+.
--debug-gpumem
Enable GPU memory stats in status bar.
--debug-gpu-shaders
Enable GPU memory stats in status bar.
--debug-gpu-force-workarounds
Enable GPU memory stats in status bar.
--debug-wm
Enable debug messages for the window manager, shows all operators in search, shows keymap errors.
--debug-all
Enable all debug messages.
--debug-io
Enable debug messages for I/O (collada, …).
--debug-fpe
Enable floating point exceptions.
--disable-crash-handler
Disable the crash handler.
--disable-abort-handler
Disable the abort handler.

Misc Options

--app-template <template>
Set the application template (matching the directory name), use default for none.
--factory-startup
Skip reading the startup.blend in the user’s home directory.
--enable-library-override
Enable Library Override features in the UI.
--enable-event-simulate
Enable event simulation testing feature bpy.types.Window.event_simulate.
--env-system-datafiles
Set the BLENDER_SYSTEM_DATAFILES environment variable.
--env-system-scripts
Set the BLENDER_SYSTEM_SCRIPTS environment variable.
--env-system-python
Set the BLENDER_SYSTEM_PYTHON environment variable.
-noaudio
Force sound system to None.
-setaudio
Force sound system to a specific device. NULL SDL OPENAL JACK.
-h, --help
Print this help text and exit.
-R
Register blend-file extension, then exit (Windows only).
-r
Silently register blend-file extension, then exit (Windows only).
-v, --version
Print Blender version and exit.
--
End option processing, following arguments passed unchanged. Access via Python’s sys.argv.

Other Options

/?
Print this help text and exit (windows only).
--debug-freestyle
Enable debug messages for Freestyle.
--verbose <verbose>
Set logging verbosity level.

Argument Parsing

Arguments must be separated by white space, eg:

blender -ba test.blend

…will exit since -ba is an unknown argument.

Argument Order

Arguments are executed in the order they are given. eg:

blender --background test.blend --render-frame 1 --render-output '/tmp'

…will not render to /tmp because --render-frame 1 renders before the output path is set.

blender --background --render-output /tmp test.blend --render-frame 1

…will not render to /tmp because loading the blend-file overwrites the render output that was set.

blender --background test.blend --render-output /tmp --render-frame 1

…works as expected.

Environment Variables

BLENDER_USER_CONFIG:
 Directory for user configuration files.
BLENDER_USER_SCRIPTS:
 Directory for user scripts.
BLENDER_SYSTEM_SCRIPTS:
 Directory for system wide scripts.
BLENDER_USER_DATAFILES:
 Directory for user data files (icons, translations, ..).
BLENDER_SYSTEM_DATAFILES:
 Directory for system wide data files.
BLENDER_SYSTEM_PYTHON:
 Directory for system Python libraries.
TEMP:Store temporary files here.
TMP:or $TMPDIR Store temporary files here.
SDL_AUDIODRIVER:
 LibSDL audio driver - alsa, esd, dma.
PYTHONHOME:Path to the Python directory, eg. /usr/lib/python.