Streamlabs Dual Output: setting up a vertical stream without rebuilding every scene

Updated August 2026. About a 7 minute read.

If you stream on Streamlabs Desktop and you want a real vertical feed for phones, the feature you're after is Dual Output. It's been in Streamlabs for a while. Twitch turned on Dual Format for everyone on June 17, 2026, and since then a lot more people have finally bothered to set it up.

This guide covers what Dual Output does and how it differs from the OBS plus Aitum Vertical route people mention online. Mostly it's about skipping the worst part, which is hand-building a vertical layout for every scene you own.

What Dual Output actually does

Dual Output gives Streamlabs Desktop two canvases at once. One is your normal horizontal 16:9. The other is a vertical 9:16 canvas at 1080x1920. You switch it on in settings, a second editor shows up, and now each scene has a horizontal arrangement and a vertical arrangement of the same sources.

That's the thing to get. It isn't an auto-crop. Streamlabs won't shrink your wide layout into a phone-shaped box. Every source in your scene gets its own position and size on the vertical canvas, and that vertical canvas starts out basically empty. The sources exist, but Streamlabs has no idea where you want them on a 1080x1920 screen. You place them yourself.

Once both canvases are set, Streamlabs streams and records them together. Desktop viewers get the wide broadcast and phone viewers get a true vertical feed instead of a letterboxed strip.

How this differs from OBS plus Aitum Vertical

Both paths land in the same place. You end up with a horizontal broadcast and a separate vertical one.

The difference is where the vertical canvas comes from. On stock OBS, the second canvas is the free Aitum Vertical plugin (the obs-vertical-canvas project). It adds a Vertical dock with its own scene list. On Streamlabs Desktop, the vertical canvas is built into the app as Dual Output, no plugin needed.

That's the pull of staying in Streamlabs. It's one program, and Dual Output is a checkbox instead of an install-and-restart routine. The catch is that Streamlabs and OBS save their scenes in different file formats, which matters in a minute.

The part everyone hates: vertical layouts for every scene

Whichever tool you pick, the vertical canvas is where the actual work sits. A phone screen is a different design problem than a monitor.

Your facecam wants the top third, sized so your face still reads at phone scale. Gameplay keeps its 16:9 shape, because stretching it looks awful, and it sits full width in the middle at roughly 1080x607. Twitch's mobile app draws its own title bar across the top and its own chat across the bottom, so anything important up there or down there gets covered. A burned-in chat box is usually redundant on vertical, since Twitch mobile already overlays chat. Wide overlay art, meaning top bars and 16:9 frames, has no vertical version, so most of it just needs hiding.

Doing that once is fine. Doing it for a five-scene setup is an evening you don't get back.

The shortcut, and the honest catch

SceneFlip is a free browser tool that reads an exported scene collection and rebuilds each scene at 1080x1920 using the rules above. Nothing uploads. Your file stays on your machine.

Now the honest part, and I won't dress it up. SceneFlip works on OBS scene collections. Streamlabs Desktop uses its own collection format, and the two aren't the same file. So you can't drop a native Streamlabs collection onto SceneFlip and expect it to read it. That's a real limit, and I'd rather say it now than have you find out after exporting.

What SceneFlip does have is a "standalone 1080x1920 collection" mode. It takes an OBS scene collection and outputs a self-contained vertical OBS collection you import straight into OBS, no Aitum canvas linking required. So the SceneFlip path fits you cleanly in a couple of situations.

1. Your scenes started life in OBS, or you keep an OBS copy around. Export that collection (Scene Collection, then Export), run it through SceneFlip in standalone mode, and import the result into OBS.
2. You're on the fence about moving your vertical workflow to OBS plus Aitum anyway. The standalone collection hands you a ready vertical layout to import and tweak.

If you're set on doing everything inside Streamlabs Dual Output, SceneFlip can't convert the Streamlabs file for you today, so that vertical canvas is a manual job in the Dual Output editor. I'm not going to overclaim it. You rebuild it by hand, or you run your layout through OBS where the tooling exists.

Either way, once you've got vertical scenes you like, turn on Dual Output (or the Aitum canvas), enable Enhanced Broadcasting in your Twitch dashboard under Settings, then Stream, and check the Twitch mobile app to confirm the vertical feed fills the screen.

A note on speed

SceneFlip is free. There's also a paid SceneFlip Pro that adds genre layout presets if you want a starting point tuned for, say, a chatting stream versus a shooter. Both live at sceneflip.com. Just remember what it eats: an OBS scene collection, not a Streamlabs one.

SceneFlip is a free tool for streamers going vertical. It runs entirely in your browser and your scene collection never leaves your machine.