Set up a Custom RTMP in vMix (Custom RTMP)

This guide shows you how to configure vMix to stream to a RTMP/RTMPS server (CDN or private server) by filling in the URL and Stream Name/Key in Streaming Settings.

1) Requirements & needed details

For a Custom RTMP destination you need these from your provider or your server:

• RTMP/RTMPS URL (e.g. rtmp://host/app or rtmps://host/app)
• Stream Name/Key (often called “Stream Key”, “Stream Name”, “Key” or a token)
• A stable upload connection (Ethernet is better than Wi?Fi)

URL:  rtmp(s)://HOST[:PORT]/APP
Key:  STREAM_NAME   (or STREAM_NAME?token=...)

Example 1 (classic RTMP)
URL: rtmp://stream.yourdomain.tld/live
Key: channel1

Example 2 (RTMPS + token)
URL: rtmps://stream.yourdomain.tld/live
Key: channel1?token=ABC123

2) Open Streaming Settings

1. In the main vMix window, locate the Stream button.
2. Click the gear icon next to Stream to open Streaming Settings.

3) Configure Custom RTMP Server (URL + Stream Key)

1. In Streaming Settings, pick a Profile (optional, useful for saving multiple destinations).
2. Under Destination, select Custom RTMP Server.
3. Fill in:
   • URL: paste the RTMP/RTMPS endpoint
   • Stream Name or Key: enter your stream key
4. If your provider requires username/password, open Advanced and enter them (only if required by your provider).
5. Click Save and Close to save.

4) Quality, encoder and recommended settings

In Quality, choose a preset that matches your upload bandwidth. The FFMPEG option is typically recommended because it supports H.264 + AAC and offers good quality and compatibility.

5) Start the stream and verify

1. Make sure your production (Preview/Output) is ready.
2. Press Stream in the main vMix window.
3. When active, the button turns red. Verify on your provider dashboard/player that the stream is received.

6) RTMPS (secure connection)

If your endpoint is RTMPS, usually it’s enough to use a URL that starts with rtmps:// (or any “secure” option provided by your service).

7) Troubleshooting

Error: “Could not connect” / can’t connect

• Re-check URL and Stream Key (no extra spaces/characters).
• If the URL includes a port (e.g. :1935), make sure it’s the correct one.
• Firewall/NAT: the most common RTMP port is TCP 1935 (if your provider uses 443/80 or another port, you must use the one they specify).
• If using RTMPS, verify certificate/port and that the endpoint supports RTMPS.

Choppy stream / dropped frames

• Lower bitrate and/or resolution (720p is more resilient than 1080p).
• Enable Hardware Encoder if available.
• Use a wired connection and stop competing uploads (backups, cloud sync, etc.).

Audio out of sync

• Keep a consistent sample rate (typically 48 kHz) and check delays on audio sources.
• Avoid very heavy filters if the machine is close to its limits.

8) FAQ

Does vMix support multiple destinations?

Yes: vMix can handle multiple streams/destinations (depending on version and configuration). If you use NVIDIA hardware encoding, keep in mind the GPU’s simultaneous encoder limits.

Do I need username/password for Custom RTMP?

It depends on the provider. Many use only URL+Key; others require credentials in “Advanced” or tokens in the Key/URL.

Why do some networks block RTMP?

On some corporate networks, port 1935 may be filtered. In that case, many providers offer endpoints on 443/80 (or RTMPS) for better compatibility.