CUB Studio docs.

Overview

CUB Studio is a free, all-in-one live streaming app for Windows. It bundles the tools most streamers otherwise run as separate apps — automation, native overlay sources, VTubing, Twitch integration, remote guests, and multistreaming — directly into the app you're already streaming from.

Installation

1. Download the installer from obs.cubsoftware.site/download.
2. Run CUB-Studio-<version>-Setup.exe. It's code-signed, but Windows SmartScreen may still show a warning until the certificate builds up download reputation — if so, click More info → Run anyway.
3. Follow the installer prompts to finish setup.
4. Sign in with Twitch from Settings → Account to enable stream-key fetch, chat, alerts, and channel-point features.

System Requirements

Scenes & Sources

Scenes, sources, and the audio mixer work the way you'd expect — scene collections and profiles, plus encoder options (NVENC, AMF, QuickSync, x264).

CUB Studio also registers a system-wide Virtual Camera ("CUB Studio Virtual Camera") so you can pipe your scene output into Zoom, Discord, or any other app that accepts a webcam.

Settings are organized into General, Stream, Output (covers both Streaming and Recording), Audio, Video, Hotkeys, Advanced — plus CUB-specific pages for Account (Twitch login) and Appearance (themes).

Overlay Sources

Unlike browser-based overlays, CUB Studio's overlay catalog is drawn natively inside the app — add one from Sources → Add like any other source, no browser or web server involved. Each has its own Properties dialog for styling (fonts, colours, sizes, animation) on top of what's listed below.

Twitch chat & alerts

Widgets & utilities

VTubing

Two native VTubing sources are built in — no separate PNGTuber or Live2D app required.

PNGTuber Avatar

Add three images — idle, talking, and muted — and pick an audio source (a mic or an existing scene source). CUB Studio switches between them based on live audio level, with a smoothing window so brief pauses between syllables don't flicker the image, and automatically shows the muted image when that source is muted.

Live2D Avatar

Load a Live2D Cubism model (.model3.json) and pick an audio source — CUB Studio lip-syncs the model's mouth parameters to the live audio level, with adjustable sensitivity and mouth-open gain.

Twitch Integration

Sign in once from Settings → Account to unlock:

• Automatic stream-key fetch — no copy-pasting keys.
• Chat — read and send messages from the built-in chat dock.
• Live event alerts — follows, subs, resubs, gift subs, bits, raids, and hype train, delivered in real time via Twitch EventSub.
• Channel points — create, edit, and delete reward, cancel/fulfil redemptions, and time out viewers.
• Polls & Predictions — live-updating results on screen as votes come in.

Your stream key and Twitch tokens are stored locally on your PC (%APPDATA%\cub-studio\cub_twitch_auth.json) — CUB SOFTWARE's servers only broker the OAuth login itself. Reconnecting Twitch after granting new permissions takes effect immediately, no app restart needed.

Automation

Under Automation in the top menu, build rules that fire one or more actions when a trigger occurs.

Triggers

Actions

Switch Scene, Show/Hide/Toggle Source, Mute/Unmute Source, Start/Stop Streaming, Start/Stop Recording, Save Replay, Send Chat Message, Wait, set a global or persistent Variable, add to a Variable, or Run C# Code for anything more advanced. A Variables manager (Automation → Variables) lists every variable so you can see and edit them without writing code.

CUB Games & the C# host

A built-in C# code host runs Streamer.bot-style scripts natively — no external app, and no separate .NET install (the runtime ships bundled). It includes:

• CUB Games hub — a full currency/economy game control panel, opened from Automation → CUB Games. It can create, edit, and delete your Twitch channel-point rewards directly, and redemptions trigger the matching game automatically once the hub is open.
• Channel Point Rewards viewer (Automation → Channel Point Rewards) — a live, auto-refreshing list of your custom rewards with a delete option and a shortcut to your Twitch dashboard.
• Command Library (Automation → Command Library) — 50+ ready-made chat commands, grouped by category; one click adds a command as C# code and creates its chat-command rule automatically.

See the Changelog for the full list of what the C# host currently supports.

Guests & Multistream

Guests

Bring remote guests into your stream from the Sources menu — guests join over a self-hosted WebRTC/RTMP relay with no stream key or website account needed on their end. Each guest source lets you turn off or customise their on-screen name label from its Properties dialog.

Multistream

Send your stream to Twitch, YouTube, and Kick simultaneously via server-side RTMP fan-out — no extra local CPU cost. Configure destinations at cubsoftware.site/apps/cub-studio/multistream-guide (invite-only, ask in Discord for access).

Encoder Benchmark

Not sure what settings to use? Settings → Output → Encoder Benchmark tests your CPU, GPU, and upload speed, then applies the best encoder, resolution, frame rate, and bitrate for your PC — whether you're streaming to Twitch or a custom RTMP destination.

Settings & Themes

CUB Studio ships with 15 built-in themes: a red default, Blue, Dark, Grey, Light, and ten extra dark variants — Emerald, Sunset, Cyberpunk, Rose, Amethyst, Ocean, Nord, Dracula, Solarized, and Coffee. Pick one in Settings → Appearance.

All local data — scenes, profiles, settings, and logs — is stored under %APPDATA%\cub-studio\.

Plugins

CUB Studio uses the standard OBS plugin format: a .dll module placed in obs-plugins\64bit\, with any accompanying data in data\obs-plugins\<plugin-name>\. Restart the app to load a newly-installed plugin, then enable or disable it any time from Tools → Plugin Manager. Browse available plugins on the Plugin Marketplace.

Auto-Updates

CUB Studio checks for updates in the background every few days. When one is available, you'll get a prompt with the choice to install it now, skip that version, or dismiss it — updates are never installed silently. Update packages are verified before installing.

FAQ

Is CUB Studio free?

Yes. CUB Studio is free to download and use.

Can I use CUB Studio alongside other streaming software?

Yes — they don't conflict at the OS level, though only one app can hold exclusive-mode capture on a source (like a fullscreen game) at a time.

Where is my data stored?

Locally, under %APPDATA%\cub-studio\ — scene collections, profiles, settings, logs, and plugin config. Nothing is uploaded except what a feature explicitly needs (e.g. your Twitch login token, used to talk to Twitch's API).

Troubleshooting

Black screen on Display/Window Capture

• Make sure Hardware-accelerated GPU scheduling is enabled in Windows GPU settings.
• Right-click CUB Studio's executable → Properties → Compatibility → Run as administrator.
• For fullscreen games, switch that source to Game Capture mode.

Stream won't start

• Verify your stream key or Twitch login in Settings → Stream / Account.
• Check that your selected encoder is supported on your GPU.
• Try lowering the output bitrate — your upload speed may be insufficient. The Encoder Benchmark in Settings → Output can pick sensible defaults for you.

An overlay source looks blank

• Right-click the source → Properties and confirm a valid audio/image/model input is selected.
• For Twitch-driven sources (labels, goals, alerts), confirm you're signed in under Settings → Account.