CastreamHelp Center
Open Castream
← Back to Help Center

Platform Guides

How to Stream to YouTube and TikTok at the Same Time

How to Stream to YouTube and TikTok at the Same Time

Your YouTube audience and your TikTok audience are two different crowds — and most creators only reach one of them. When you stream to YouTube and TikTok at the same time, one broadcast feeds both: the long-form crowd that watches on TV and desktop, and the swipe-fast crowd living on their phones.

Castream makes this a one-tap thing once your destinations are connected. Here's the full setup.

✅ What You'll Need

  • A Castream account (mobile app or web)
  • A YouTube channel with live streaming enabled
  • A TikTok account with LIVE access and RTMP availability (you'll need your Server URL and Stream Key)
  • A stable internet connection — Wi-Fi or strong mobile data

TikTok doesn't hand out RTMP access to every account. If you can't find a Server URL or Stream Key in your TikTok LIVE setup area, your account doesn't have it yet — you can still stream to YouTube while you wait. Our TikTok RTMP guide walks through exactly where to look.

📲 Step 1 — Connect YouTube

  1. Open the Castream app
  2. Go to Settings → Destinations
  3. Tap YouTube
  4. Sign in with your Google account and authorize Castream
  5. Pick the channel you want to stream to
  6. Save the destination

That's it — YouTube stays connected until you remove it, so this is a one-time step.

📲 Step 2 — Connect TikTok (RTMP)

TikTok connects differently: instead of a login button, you paste in RTMP credentials.

  1. Open TikTok and head to the LIVE setup area
  2. Look for an option like Stream key, Go LIVE from desktop, or Streaming software
  3. Copy your TikTok Server URL and Stream Key
  4. Back in the Castream app, go to Settings → Destinations
  5. Tap TikTok
  6. Paste the Server URL and Stream Key, then save

⚠️ Keep your TikTok stream key private — never share it or post screenshots of it. And heads-up: TikTok keys can expire or change between sessions. If a stream suddenly fails to connect, generate a fresh pair in TikTok and update the destination in Castream.

Don't see the RTMP option in TikTok? You're not alone — this is the most common blocker for this combo. A few things that help: make sure your account is 18+, in good standing, and has LIVE access (not just the ability to watch). Some creators report the option appearing after they've gone live from the mobile app a few times. There's no official follower threshold TikTok publishes, and no way to force it — if it's not there, run the YouTube leg solo and check back in a week or two. You lose nothing by having the destination saved and ready.

🎬 Step 3 — Go Live from the App

  1. Open Castream and tap Go Live
  2. Toggle YouTube ON
  3. Toggle TikTok ON
  4. Add your title (pro tip: Castream Web can generate titles and descriptions with AI if you're blanking)
  5. Tap Go Live — Castream starts sending your stream to both platforms
  6. Important: open TikTok's LIVE setup page and confirm the broadcast there — TikTok usually requires you to hit Go LIVE inside TikTok before viewers can see you

You're now live in two places at once, from one phone. 📡

🖥️ Alternative: Stream from OBS via Castream Web

If you'd rather run a desktop setup — overlays, multiple cameras, screen share — send OBS into Castream first, then let Castream forward it to YouTube and TikTok.

  1. Log in to Castream Web
  2. Go to Destinations and make sure YouTube and TikTok are connected (same steps as above)
  3. Find your Castream RTMP URL and Stream Key in the web dashboard
  4. In OBS, go to Settings → Stream, set Service to Custom, and paste them in
  5. Start streaming in OBS
  6. Open the Go Live Dashboard in Castream Web, select YouTube + TikTok, and click Go Live
  7. Confirm the broadcast inside TikTok

Full walkthrough: How to Stream to YouTube, Twitch & More Using OBS and Castream.

⚙️ Settings That Work for Both Platforms

Here's the one real tension in this combo: YouTube viewers expect horizontal video, TikTok viewers expect vertical. You have to pick a lane:

  • Vertical (9:16, 1080 × 1920) — best if TikTok is your priority. It still works on YouTube (mobile viewers get a full-screen experience), but desktop YouTube viewers will see pillarboxing.
  • Horizontal (16:9, 1920 × 1080) — best if YouTube is your priority. TikTok will show it letterboxed and small, which hurts watch time.

Most creators running this combo go vertical — TikTok is where the discovery happens, and YouTube still counts the watch time. Either way:

  • 30 FPS is the sweet spot for both
  • Keep bitrate in the 4–8 Mbps range if your connection allows it
  • Use Wi-Fi or a wired connection for the sending device when possible
  • Test your audio before going live — bad audio kills retention on both platforms

💡 Making the Combo Actually Work

Going live on both platforms is the easy part. Getting both audiences to stay takes a little intention:

  • Say hello to both chats by name. "What's up YouTube, what's up TikTok" in your first 30 seconds tells each audience you see them. Viewers who feel invisible leave.
  • Design for the small screen. Text overlays, whiteboards, and gameplay HUDs that read fine on a TV can be unreadable on a phone. If TikTok matters to you, keep key visuals big and centered.
  • Repurpose after. Your YouTube stream becomes a VOD automatically; clip the best 60 seconds for a TikTok post later. One live session, three pieces of content.
  • Mind the delay. TikTok LIVE typically runs a few seconds behind YouTube. Don't try to run real-time polls across both chats — you'll confuse everyone.

Pair this combo with our mobile streaming setup guide for gear and connection tips that apply to any multistream.

⚠️ Things to Watch Out For

  • TikTok may end or restrict your LIVE mid-stream — Castream can't restart it for you, so keep the TikTok app handy
  • Chat lives in two places. Comments on YouTube and TikTok are separate; Castream Web's unified chat view helps you follow both without juggling apps
  • Your TikTok stream key might change between sessions — if TikTok stops receiving video, refresh the key first
  • Content rules differ. Something fine on YouTube might trip TikTok's LIVE moderation. When in doubt, follow the stricter platform's rules

✅ Quick Checklist

  • YouTube connected as a destination
  • TikTok Server URL + Stream Key pasted and saved
  • Both destinations toggled ON before going live
  • Broadcast confirmed inside TikTok
  • Orientation chosen (vertical recommended for this combo)
  • Audio tested, connection stable

One stream, two audiences. Once the destinations are saved, the whole thing is literally two toggles and a button.