OSC

OSC is a way to get different devices and applications to talk to each other. VRChat announced on February 16th 2022 OSC for avatars. This feature is commonly used by body-, eye- and face trackers to communicate with VRChat, as well as by other applications that automate Avatar parameters.

OSCQuery

OSCQuery is a protocol to connect OSC applications together more easily. Information on how to connect with VRChat with OSCQuery is available on the VRChat OSCQuery GitHub Wiki. VRChat also provides a C# library on GitHub.

Some of the community made OSCQuery libraries:

• TypeScript with example scripts on GitHub by Jangxx - node-oscquery.
• Python with examples on the GitHub readme.md - vrchat_oscquery. An older variant that's more descriptive - tinyoscquery.
• Rust implementation with baseline functionality - oscquery.

OSC feature set

OSC enables control and monitoring of multiple systems within VRChat, including input controls, avatar parameters, chatbox functionality, and camera systems such as the Camera Dolly.

OSC messages

Many of VRChat's OSC endpoints can accept multiple values in one message, and each value must be one of certain types:

Name	Type	Description
int	i	32-bit signed integer (big-endian)
float	f	32-bit IEEE 754 single-precision float (big-endian)
boolean	T or ,F	Boolean true or false, respectively
string	s	ASCII text (some endpoints explicitly accept UTF-8 encoded text)

In an OSC message, the string specifying the types of the message's values begins with a , followed by one character for each type, and in the following tables, the type of the whole message is listed.

Sometimes, when an OSC message has only one parameter, VRChat may accept an equivalent value of a different type:

boolean	int	float
false	0	0.0
true	1	1.0

For example, if the Avatar parameter /avatar/parameters/TurboEncabulator is a boolean, sending any of
/avatar/parameters/TurboEncabulator ,T,
/avatar/parameters/TurboEncabulator ,i 1, or
/avatar/parameters/TurboEncabulator ,f 1.0 as a message will set the parameter to true.

VRChat accepts and processes messages sent inside of OSC bundles, but does not itself send any bundles.

Avatar

OSC provides read and write access to avatar parameters, enabling real-time control of avatar expressions, animations, and custom behaviors. Parameters are accessed through /avatar/parameters/<ParameterName> addresses and support integer, float, and boolean data types. Custom Avatar parameter names and behaviors are defined by individual avatar creators, but there are a number of reserved parameters. All Avatar custom OSC endpoints are read-write, but all Avatar reserved OSC endpoints are read-only unless otherwise specified.

Address	Type	Description
/avatar/change	,s	read-write Current user avatar id
/avatar/parameters/VRCEmote	,i	read-write Default animation (1 to 16) *
/avatar/parameters/VRCFaceBlendV	,f	read-write *
/avatar/parameters/VRCFaceBlendH	,f	read-write *
/avatar/parameters/PreviewMode	,i	1: Avatar in menu preview, otherwise 0 (OSC: always 0)
/avatar/parameters/IsOnFriendsList	,T	Whether the local user is friends with the remote user with this avatar (OSC: always false)
/avatar/parameters/IsAnimatorEnabled	,T	Whether the animator is enabled
Gesture
/avatar/parameters/GestureRightWeight	,f	Weight for right hand gesture
/avatar/parameters/GestureLeftWeight	,f	Weight for left hand gesture
/avatar/parameters/GestureRight	,i	Right hand gesture
/avatar/parameters/GestureLeft	,i	Left hand gesture
Scaling
/avatar/parameters/ScaleModified	,T	Whether the avatar scale has been changed from the default height
/avatar/parameters/ScaleFactor	,f	Avatar current height / default height
/avatar/parameters/ScaleFactorInverse	,f	Reciprocal of above (default height / current height)
/avatar/parameters/EyeHeightAsMeters	,f	Avatar current eye height in meters
/avatar/parameters/EyeHeightAsPercent	,f	Linear interpolation of avatar current eye height between default limits (e.g., 0.0: 0.2 meters, 0.5: 2.6 meters, 1.0: 5.0 meters)
Sound
/avatar/parameters/Viseme	,i	The viseme currently shown
/avatar/parameters/Voice	,f	Microphone volume (0.0: silent, 1.0: loudest)
/avatar/parameters/Earmuffs	,T	Whether the user has Earmuff Mode enabled
/avatar/parameters/MuteSelf	,T	Whether the user has muted themselves
Player
/avatar/parameters/AFK	,T	Whether the user is AFK
/avatar/parameters/InStation	,T	Whether the user is in a station
/avatar/parameters/Seated	,T	Duplicate of above, not "seated mode" vs. "standing mode"
/avatar/parameters/VRMode	,i	1: VR mode, otherwise 0
/avatar/parameters/TrackingType	,i	Number of currently tracked points
Positioning
/avatar/parameters/Grounded	,T	Whether the user is touching the floor int the world
/avatar/parameters/Upright	,f	Heuristic for how "upright" you are (0.0: prone, 1.0: standing straight up)
/avatar/parameters/AngularY	,f	Rightward angular velocity
/avatar/parameters/VelocityX	,f	Rightward velocity in m/s
/avatar/parameters/VelocityY	,f	Upward velocity in m/s
/avatar/parameters/VelocityZ	,f	Forward velocity in m/s
/avatar/parameters/VelocityMagnitude	,f	Total magnitude of velocity: √( VelocityX ² + VelocityY ² + VelocityZ ² )

* technically not required/built-in, but these parameters are in the default animator and are almost always present

Input

OSC can trigger VRChat input actions by sending messages to /input/* addresses. This includes movement controls, view rotation, jumping, voice toggling, and VR-specific interactions. All Input OSC endpoints are write-only.

Axes

These expect a float from -1 to 1 to control things like movement. They must be reset to 0 when not in use: a /input/Vertical ,f 1 message without a corresponding /input/Vertical ,f 0 will continue to move you forward forever.

Address	Type	Description	+1	-1
/input/Horizontal	,f	Player movement	right	left
/input/Vertical	,f	Player movement	forward	backward
/input/LookHorizontal	,f	Player rotation *	right	left
/input/LookVertical †	,f	Player rotation	up	down
/input/SpinHoldCwCcw	,f	Held item rotation	clockwise	counter-clockwise
/input/SpinHoldUD	,f	Held item rotation	up	down
/input/SpinHoldLR	,f	Held item rotation	left	right
/input/MoveHoldFB	,f	Held item movement	forward	backward
/input/UseAxisRight ‡	,f	Held item use
/input/GrabAxisRight ‡	,f	Held item grab

Buttons

These expect an boolean of true for "pressed" and false for "released". For compatability, they also accept ints of 0 and 1, equivalent to false/"released" and true/"pressed" respectively. They must be reset to false when not in use: a /input/MoveForward ,T message without a corresponding /input/MoveForward ,F will continue to move you forward forever. They must also be reset to false before they can be used again: sending a /input/Jump ,T and then another /input/Jump ,T without a /input/Jump ,F between them will only result in a single jump.

Address	Type	Description
/input/MoveForward	,T	Move forward
/input/MoveBackward	,T	Move backward
/input/MoveLeft	,T	Move left
/input/MoveRight	,T	Move right
/input/LookLeft	,T	Turn left *
/input/LookRight	,T	Turn right *
/input/Jump	,T	Jump (if supported by the world)
/input/Run	,T	Run (if supported by the world)
/input/ComfortLeft	,T	Snap-Turn to the left (VR only)
/input/ComfortRight	,T	Snap-Turn to the right (VR only)
/input/GrabRight	,T	Grab item highlighted by right hand
/input/UseRight	,T	Use item held in right hand
/input/DropRight	,T	Drop item held in right hand
/input/GrabLeft	,T	Grab item highlighted by left hand
/input/UseLeft	,T	Use item held in left hand
/input/DropLeft	,T	Drop item held in left hand
/input/PanicButton	,T	Enable Safe Mode
/input/QuickMenuToggleLeft	,T	Toggle Quick Menu for left hand
/input/QuickMenuToggleRight	,T	Toggle Quick Menu for right hand
/input/ToggleSitStand †	,T	Toggle between Sitting and Standing
/input/AFKToggle †	,T	Toggle AFK mode
/input/Voice	,T	Toggle Microphone (in Push-To-Talk Mode, false = "muted" and true = "unmuted")
/input/ShowDebugInfo0 †	,T	Displays some debugging visualizations for VRC_UiShapes (interactable UIs) ⁑
/input/ShowDebugInfo1	,T	Displays information about loaded asset bundles (mostly irrelevant to world development)
/input/ShowDebugInfo2	,T	Displays the current build of VRChat that you are using, along with your FPS
/input/ShowDebugInfo3	,T	Displays your output log
/input/ShowDebugInfo4	,T	Displays various stats about other users
/input/ShowDebugInfo5	,T	Displays some graphs related to networking
/input/ShowDebugInfo6	,T	Displays all the networked objects in your world, along with various stats ⁑
/input/ShowDebugInfo7	,T	Overlays visual representations of every PhysBone and Contact in the world near the local player ⁑
/input/ShowDebugInfo8	,T	Overlays a panel on top of every synced object in the world; Each panel displays various stats about that specific object ⁑
/input/ShowDebugInfo9	,T	Displays debug stats for every player in the instance at their feet ⁑

The /input/ShowDebugInfo[0-9] endpoints are for World Debug Views

* smooth-turn in Desktop; will snap-turn in VR when value 1 or true if Comfort Turning is on

⁑ only accessible to the world creator unless they have turned on "World Debugging" via the website

Chatbox

Address	Type	Description
/chatbox/input	,sTT	Set Chatbox content
	1st parameter s	Text to input/send (144 character, 9 line maximum; supports UTF-8 text)
	2nd parameter T	Whether to send immediately, otherwise open the keyboard and populate the text
	3rd parameter T	Whether to trigger the notification SFX (optional, defaults to true; only applicable if text is sent immediately)
/chatbox/typing	,T	Set Chatbox typing indicator visibility (the ...)

Tracking

All Tracking and Eye Tracking OSC endpoints are write-only unless otherwise specified. Sending the /tracking/trackers/head/... values is optional; if supplied, VRChat will use them as the frame of reference for the other OSC trackers. After 10 seconds without receiving data, eye tracking behavior will revert to default (auto look / auto blink). This timeout is separate for eyelids and eye-look.

Address	Type	Description
/tracking/trackers/[1-8]/position	,fff	The position of the tracker
	1st parameter f	Cartesian X coordinate
	2nd parameter f	Cartesian Y coordinate
	3rd parameter f	Cartesian Z coordinate
/tracking/trackers/[1-8]/rotation	,fff	The rotation of the tracker
	1st parameter f	Euler X angle
	2nd parameter f	Euler Y angle
	3rd parameter f	Euler Z angle
/tracking/trackers/[1-8]/position	,fff	The position of the headset (see .../position above)
/tracking/trackers/[1-8]/rotation	,fff	The rotation of the headset (see .../rotation above)
/tracking/eye/EyesClosedAmount	,f	How closed the eyes are (0.0: fully open, 1.0: fully closed)
/tracking/eye/CenterPitchYaw	,ff	Pitch and yaw for automatic raycast (eyes look at hit location)
	1st parameter f	Euler X angle
	2nd parameter f	Euler Y angle
/tracking/eye/CenterPitchYaw	,ff	Pitch, yaw, and distance for raycast (eyes look at vector position)
	1st parameter f	Euler X angle
	2nd parameter f	Euler Y angle
	3rd parameter f	Raycast distance
/tracking/eye/CenterVec	,fff	Headset-local normalized vector for automatic raycast (eyes look at hit location)
	1st parameter f	Cartesian X coordinate
	2nd parameter f	Cartesian Y coordinate
	3rd parameter f	Cartesian Z coordinate
/tracking/eye/CenterVecFull	,fff	Headset-local vector for raycast (eyes look at vector position)
	1st parameter f	Cartesian X coordinate
	2nd parameter f	Cartesian Y coordinate
	3rd parameter f	Cartesian Z coordinate
/tracking/eye/LeftRightPitchYaw	,ffff	Pitch and yaw for each eye individually
	1st parameter f	Euler X angle for left eye
	2nd parameter f	Euler Y angle for left eye
	3rd parameter f	Euler X angle for right eye
	4th parameter f	Euler Y angle right eye
/tracking/eye/LeftRightVec	,fff	Headset-local normalized vectors for each eye individually
	1st parameter f	Cartesian X coordinate for left eye
	2nd parameter f	Cartesian Y coordinate for left eye
	3rd parameter f	Cartesian Z coordinate for left eye
	4th parameter f	Cartesian X coordinate for right eye
	5th parameter f	Cartesian Y coordinate for right eye
	6th parameter f	Cartesian Z coordinate for right eye
/tracking/vrsystem/head/pose †	,ffffff	The read-only system pose for the headset
	1st parameter f	Cartesian X coordinate
	2nd parameter f	Cartesian Y coordinate
	3rd parameter f	Cartesian Z coordinate		4th parameter f	Euler X angle
	5th parameter f	Euler Y angle
	6th parameter f	Euler Z angle
/tracking/vrsystem/leftwrist/pose †	,ffffff	The read-only system pose for the left wrist (see >.../head/pose above)
/tracking/vrsystem/rightwrist/pose †	,ffffff	The read-only system pose for the right wrist (see >.../head/pose above)

The coordinate system used is generally the same as the left-handed Unity coordinate system.

For Cartesian coordinate vectors, distances are in meters of real-world space.

• +X is right, -X is left
• +Y is up, -Y is down
• +Z is forward, -Z is backward

For Euler angle vectors, angles are in degrees and are applied in (ZXY) order internally when converting to a quaternion.

• +X is pitch down, -X is pitch up
• +Y is yaw right, -Y is yaw left
• +Z is roll left/counter-clockwise, -Z is roll right/clockwise

User Camera

All User Camera OSC endpoints are read-write unless otherwise specified.

Address	Type	Description
/usercamera/Mode	,i	Camera mode	0: Off 1: Photo 2: Stream 3: Emoji 4: Multilayer 5: Print 6: Drone
/usercamera/Pose	,ffffff	Camera position & rotation	read-only see /tracking/vrsystem/head/pos above

Actions

Address	Type	Description
/usercamera/Close	,T	Close camera Equivalent to /usercamera/Mode ,i 0	write-only see buttons
/usercamera/Capture	,T	Take a photo	write-only see buttons
/usercamera/CaptureDelayed	,T	Take a timed photo	write-only see buttons

Toggles

Address	Type	Description
/usercamera/ShowUIInCamera	,T	UI mask
/usercamera/LocalPlayer	,T	Local Player mask
/usercamera/RemotePlayer	,T	Remote Players mask
/usercamera/Environment	,T	Environment mask
/usercamera/GreenScreen	,T	Greenscreen
/usercamera/Lock	,T	Camera lock
/usercamera/SmoothMovement	,T	Smoothed behavior
/usercamera/LookAtMe	,T	Look-At-Me behaviour
/usercamera/AutoLevelRoll	,T	Auto-level roll behavior
/usercamera/AutoLevelPitch	,T	Auto-level pitch behavior
/usercamera/Flying	,T	Flying
/usercamera/TriggerTakesPhotos	,T	Trigger takes photos
/usercamera/DollyPathsStayVisible	,T	Dolly path visiblity while animating
/usercamera/AudioFromCamera	,T	Audio from camera
/usercamera/ShowFocus	,T	Focus overlay
/usercamera/Streaming	,T	Spout stream
/usercamera/RollWhileFlying	,T	Roll while flying behavior
/usercamera/OrientationIsLandscape	,T	Image orientation

Sliders

Address	Type	Description	Default	Minimum	Maximum
/usercamera/Zoom	,f	Zoom	45	20	150
/usercamera/Exposure	,f	Exposure	0	-10	4
/usercamera/FocalDistance	,f	Focal distance	1.5	0	10
/usercamera/Aperture	,f	Aperture	15	1.4	32
/usercamera/Hue	,f	Greenscreen hue	120	0	360
/usercamera/Saturation	,f	Greenscreen saturation	100	0	100
/usercamera/Lightness	,f	Greenscreen lightness	60	0	50
/usercamera/LookAtMeXOffset	,f	0	-25	25
/usercamera/LookAtMeYOffset	,f	Look-At-Me Y offset	0	-25	25
/usercamera/FlySpeed	,f	Fly speed	3	0.1	15
/usercamera/TurnSpeed	,f	Turn speed	1	0.1	5
/usercamera/SmoothingStrength	,f	Smoothing strength	5	0.1	10
/usercamera/PhotoRate	,f	Dolly photo capture rate	1	0.1	2
/usercamera/Duration	,f	Dolly duration	2	0.1	60

Dolly

All Dolly OSC endpoints are write-only unless otherwise specified.

Address	Type	Description
/dolly/Import	,s	Import dolly path from a JSON file
/dolly/Export	,s	Export current dolly path to a JSON file Emits an OSC message when export is complete
/dolly/ExportLocal	,s	As above, but exports all points as local
/dolly/PlayDelayed	,f	Play an animation after a delay (in seconds)
/dolly/Play	,T	Play or stop an animation Skip delay or cancel a delayed animation Emits an OSC message when animation state changes	read-write

Errata

† Missing from the VRChat Docs page, but present in the client OSCQuery response

‡ Present on the VRChat Docs page, but missing from the client OSCQuery response

OSC ports

VRChat uses two UDP ports for OSC communication, one TCP port for an OSCQuery HTTP server on localhost (127.0.0.1), and one UDP port for mDNS Service Discovery:

Port	Direction	Purpose
UDP 9000	Send → VRChat	Your application sends messages to VRChat
UDP 9001	Receive ← VRChat	Your application receives messages from VRChat
TCP variable	HTTP ↔ VRChat	Your application gets OSCQuery data from VRChat
UDP 5353	mDNS ↔ VRChat	multicastDNS Service Discovery

You can manually find the port numbers for these features by searching the current log file for a line that looks like
2025.01.02 03:04:05 Debug - Advertising Service VRChat-Client-A1B2C3 of type OSCQuery on 42069 or
2025.01.02 03:04:05 Debug - Advertising Service VRChat-Client-A1B2C3 of type OSC on 9000

Resources

• OSC Overview on the VRChat Documentation
• Full OSCQuery proposal and how it functions while including example code
• Euler angles visualizer (the coordinate system is not exactly like Unity, so negate the Euler X angle and set the order to ZXY)