Throwing lets viewers hurl objects at your VTube Studio model. The object flies across the screen, hits the model, and the model gets knocked back, plays an expression, or is even knocked clean out of frame.
What it solves
For a VTuber there are surprisingly few ways for viewers to physically reach you — chat is text, tips are numbers, both at a remove. Throwing is one of the few interactions that actually moves the model: what they threw, where it landed, how far you got pushed are all visible, and your reaction is the content.
Getting started
- Add the throwing widget's OBS URL as a browser source.
- Enable the API in VTube Studio and enter the connection address (usually the same machine).
- Adjust the hit zone so it fits your model.
- Create throwable items: image, sound, and the reaction on impact.
Hits and reactions
The hit zone is an ellipse that follows the model's anchor, sized as a proportion of the screen height — so recalibrate it after swapping models or changing scale. On impact the model can be knocked back, trigger a VTube Studio hotkey (an expression, say), and automatically fly back to its original position after a set number of seconds.
Common misconceptions
- The widget connects directly to VTube Studio on your machine, not through our servers. Model position and impact reactions are handled locally, so nothing happens if VTS isn't running.
- "Knocked out" is measured by how far the model's centre passes the screen edge, not by how it looks. The model is positioned by its centre, so scaled-up models need a larger value — otherwise it stops while still clearly visible.
- The return delay counts from when the throwing stops. It won't snap back mid-barrage, so a sustained volley doesn't get interrupted.
- Toggle-style hotkeys need a restore delay. That fires the same hotkey a second time to undo it; for hotkeys that revert on their own when the animation finishes, leave it at 0.
- Images accept http(s) URLs only — not data: URLs. GIFs animate, but a cross-origin file needs CORS permission from the host.
- Items over your plan's limit aren't pushed to the widget. They stay in the list but won't appear on screen — delete other items or upgrade to restore them.
Settings
Physics, hit zone, reaction and VTube Studio settings. Changes apply and save instantly to the connected widget.
Triggers are automation rules with a Throwing action. Cooldowns, permissions and advanced conditions are edited in Automated messages.
The text below is taken from the in-app help, so it stays in sync with the actual interface.
| Setting | What it does |
|---|---|
| Hit particles | Show a particle burst when an item hits the model. |
| Default burst interval (ms) | Delay between items in a multi-throw. 0 uses no extra delay. |
| Head flinch | Shake the head via parameter injection when hit. |
| Knockback | Push the model when hit; behavior depends on the knockback mode below. |
| Return delay after hits stop (s) | The model flies back to its original spot this many seconds after the hits stop — it won't return mid-barrage, even when already knocked off-screen. |
| Knock-out distance | How far past the screen edge the model's center must be pushed to count as knocked out (1 = just past the edge, 5 = far). The model is positioned by its center — increase this for large or zoomed-in models, or it will stop while still visible. |
| VTS hotkey ID | Optional VTube Studio hotkey triggered on hit (e.g. an expression). |
| Hotkey restore delay (s) | For toggle-type hotkeys: triggers the same hotkey again after this many seconds to restore it; while the effect is active it won't re-trigger, and further hits postpone the restore. 0 = no auto-restore (animations that end on their own, or looping hotkeys, don't need it). |
| Connect VTube Studio | The widget connects to VTube Studio on the streaming PC for model position and hit reactions. |
| VTS API address | Usually ws://127.0.0.1:8001 (VTube Studio on the same PC as OBS). |
| Image URL | http(s) URL only (data: URLs are not accepted); GIF plays animated (needs CORS cross-origin). |
| Sound file URL | http(s) URL to a browser-decodable audio file (wav/mp3/ogg). |
| Weight × | Heavier items fly slower but hit harder. |
| Over limit | This item exceeds your plan's item limit and won't be pushed to the widget; delete other items or upgrade your plan to restore it. |
| Calibration marker | Show the anchor cross (green) and hit-zone ellipse (red) on the widget. The cross is the model center reported by VTS — on full-body models it often sits near the hips, and can be low or even off-screen when only the upper body is shown. Use Offset to bring the cross to the character's chest, then use the hit-zone settings to cover the part that should get hit. |
| Zoom follow | How strongly the offset and hit zone follow when you zoom the model in VTS — drifts away after zooming → increase; overshoots → decrease. |
| Enable Throwing | When off, throwing triggers and the OBS widget stay inactive. |
Other notes
- The hit zone is an ellipse that follows the model anchor. Sizes are relative to the screen height.
- Calibration maps VTS model coordinates to screen pixels; changes apply instantly — turn on the marker and adjust against your OBS view (without VTS the marker shows the fixed anchor).
- Calibration, hit zone, VTS hotkey and knockout edge are saved per VTube Studio model (up to 10); switching to a saved model applies its profile automatically, unsaved models use the global defaults.
- Hotkey and knockout edge are per-model fields; adjustments are saved to this model.
- Viewers throw items at your Live2D model, which reacts on impact (requires VTube Studio)
Other settings
These settings have no additional help text in the dashboard; only their names are listed here.
- Reset to defaults
- Quick apply
- Gentle
- Standard
- Wild
- Physics
- Throwing
- Hit zone
- Hit reaction
- Audio
- VTube Studio
- Gravity (px/s²)
- Throw speed (px/s)
- Max spin (deg/s)
- Item base size (px)
- Max concurrent items
- Bounciness
- Spawn sides
- Left
- Right
- Top
- Bottom
- Hit zone half width
- Hit zone half height
- Hit zone Y offset
- Reaction strength
- Knockback mode
- Bounce back
- Cumulative (can knock off-screen)
- Knockback strength
- Return time (s)
- Hotkey chance
- Sound effect volume
- VTS authorization saved: reloading the widget will not ask again.
- Not authorized yet: the first connection pops an authorization dialog in VTube Studio.
- Step-by-step guide
- How to connect VTube Studio
- Open VTube Studio, click the gear icon (⚙) in the top-left to open Settings, then find the "VTube Studio Plugins" panel and turn on the option to start the API (allow plugins). The port defaults to 8001 — make sure it matches the "VTS API address" field below.
- Once the status turns green and shows the API has started and is running, VTube Studio is ready on its side.
- Back on this page, turn on "Connect VTube Studio". VTube Studio will pop up a plugin authorization dialog — find "ChiwaBots Throwing" and click Allow to finish. You only need to authorize once; it won't ask again after restarting VTube Studio.
- Add item
- No items yet.
- Upgrade to Pro for a higher item limit.
- Name
- Sound
- Size ×
- Volume ×
- Enabled
- Image source
- Built-in art
- Twitch emote
- Media library / custom URL
- Built-in art
- Pick an emote
- Preview
- None
- Splat
- Thud
- Bonk
- Clang
- Media library / custom sound…
- Open Automated messages
- Quick create
- No throwing triggers yet.
- New throwing trigger
- When to throw?
- No items yet — add some on the Items tab first.
- Name
- Trigger
- Fired
- Enabled
- Calibration guide
- Calibration & hit zone setup
- Turn on the Calibration marker below — your OBS widget then shows a green crosshair (the model center reported by VTS) and a dashed red ellipse (the hit zone).
- Drag Offset Y (px) to move the green crosshair onto the character's neck or chest; it's usually negative, most often between -200 and -600 depending on the model.
- Back in Hit zone, adjust Hit zone half height and Hit zone half width so the dashed red ellipse hugs the model's outline and covers the area you want hit.
- Test & calibration
- Test throw
- Test throw ×100
- Offset X (px)
- Offset Y (px)
- Return model now
- Model profiles
- Current model
- No model detected (OBS widget or VTube Studio not connected)
- Has profile
- Using global defaults (auto-saved on adjust)
- Saved models
- Per-model field — adjustments are saved to this model
- Tomato
- Tuna can
- Slipper
- Baseball
- Paper ball