StreamTranslateYou can use StreamTranslate without OBS through a browser microphone or a supported phone app’s extra RTMP destination. Twitch viewers can read captions in the enabled StreamTranslate extension; YouTube can receive a separate native caption feed. An overlay is another option when your streaming app supports browser widgets.
Start with the audience display.
Captioning has two connections: audio in and captions out. A caption URL displays text; it does not supply your microphone audio or start your video broadcast.
Swipe the table to compare all columns.
| You want | Use | Requirement |
|---|---|---|
| Different languages for Twitch viewers | StreamTranslate Twitch extension | You enable it on your channel and connect audio. |
| A YouTube CC track | YouTube caption delivery | Configure the broadcast’s caption-ingestion URL. |
| Captions visible inside the video | Browser Source URL | Your streaming app must support a web overlay. |
Use your microphone and the Twitch extension.
- Enable the channel extension. Install StreamTranslate CC, link the correct Twitch account and activate it as a video overlay.
- Connect your microphone. In Twitch setup or Control, choose the mic and spoken language, allow microphone access and press Go Live.
- Start your video separately. Keep the capture page open. Viewers use the extension’s language controls on your live channel.
This route does not need an OBS plugin or Browser Source. You still need a way to broadcast video to Twitch. Follow the full Twitch setup for linking and verification.
Send audio from a supported phone app.
In Control or Twitch setup, select IRL Mode and your app. Add StreamTranslate as an extra RTMP destination, keeping your normal video destination enabled. Captions begin when that audio feed arrives.
- Moblin: add the full StreamTranslate RTMP URL in Multi streaming.
- Larix: use a separate Audio only connection for StreamTranslate; keep video and audio enabled for Twitch.
- PRISM Mobile: add Custom RTMP with the separate URL and key. Multi-streaming requires PRISM Plus.
- TVU Go: add RTMP Push. Our setup guide covers the tested Unlimited route.
Moblin, PRISM and TVU send an additional audio/video feed; Larix can send only audio. Allow for the extra mobile data and upload bandwidth. Follow your app’s IRL instructions before starting. IRL Pro and some other setups still need a receiving OBS computer.
Send captions separately from the video.
YouTube accepts captions over HTTP, so the caption feed does not have to come from OBS. Keep your usual video software or phone app, and connect its audio to StreamTranslate through a supported route.
- Open the intended broadcast in YouTube Studio. Use Normal latency, enable Closed captions and choose POST captions to URL.
- Copy that broadcast’s captions ingestion URL into Control → YouTube captions.
- Choose the output language in both places, enable delivery, then test CC on the matching watch page.
This connection sends one chosen caption language, not a menu of translations. The caption URL and video destination must refer to the same broadcast. See StreamTranslate’s YouTube setup and YouTube’s delivery requirements.
A web overlay can also work without OBS.
Moblin, Larix, PRISM and TVU have browser-overlay routes documented in the IRL Hub. Add your Browser Source URL to the supported web widget, position it, and leave the StreamTranslate audio connection running.
These captions become part of the outgoing picture. You choose the language and appearance; everyone sees that same layer. The RTMP URL and Browser Source URL have different jobs and are not interchangeable.
Using an overlay alongside the Twitch extension can show two caption layers. Choose deliberately. Do not assume another streaming app supports web overlays just because it accepts an RTMP destination.
Rehearse the complete route.
Speak a few sentences through the actual microphone, open the real viewer page and check the language, timing and placement. For Twitch, try a second viewer window in another language. For YouTube, verify the CC button on the correct broadcast.
When finished, end browser microphone capture in Control or stop the StreamTranslate RTMP destination in your phone app. Hiding the text or stopping only the video destination may leave audio capture running.
Caption timing varies with speech, connection and playback. Streamer usage follows the selected plan and language-hour allowance; viewers sharing a translation language do not multiply that language’s time.
Quick answers.
Does a Browser Source URL listen to my phone?
No. It displays captions. A supported RTMP connection, browser microphone or OBS audio filter must supply the speech separately.
Can every phone streaming app do this without OBS?
No. It needs the required additional audio or RTMP output. Some setups, including our documented IRL Pro route, use a receiving home or cloud OBS instance.
Are these Twitch native closed captions?
The StreamTranslate Twitch extension has its own controls. Twitch native CC is a different output. A web overlay is text rendered into the video.
Do I need to install a new desktop app?
Browser microphone capture does not require a StreamTranslate desktop app. Phone workflows use the supported streaming app you configure; check its plan and output requirements.
Choose your next step.
Sources and further reading
Setup details reviewed October 28, 2026. Platform and device support can change; check the linked instructions for your setup.