The short answer
RTMP normally sends the live stream unencrypted. RTMPS carries the same RTMP data stream inside a TLS-encrypted connection. That protects video, audio, and stream key better on the way to the server.
In this guide
1. What are RTMP and RTMPS?
RTMP is a persistent, TCP-based transport for audio, video, and metadata. In live streaming, it is mostly used today as an ingest protocol: OBS, a hardware encoder, or a streaming app sends the finished signal to a platform or your own server.
RTMPS does not change the video content itself. It adds a TLS layer, much like the difference between HTTP and HTTPS. The server identifies itself with a certificate and the connection is encrypted.
2. RTMP and RTMPS side by side
| Feature | RTMP | RTMPS |
|---|---|---|
| Transport | RTMP over TCP | RTMP inside a TLS connection |
| Encryption | Normally no transport encryption | Video, audio, metadata, and stream key are encrypted in transit |
| Typical URL | rtmp://server.example/live | rtmps://server.example/live |
| Common port | TCP 1935 | Often TCP 443; the provider may specify a different port |
| Certificate | Not required | Valid TLS certificate and matching hostname required |
| Compatibility | Very broad, including older encoders | Encoder and server must support RTMPS |
| Recommended use | Internal network, lab, compatibility exception | Public internet and platform ingest |
The URLs are only patterns, not clickable server addresses. The port numbers are typical values too, not a fixed rule. What counts is always the full address your server or platform gives you.
3. Which one should I use?
- Straight to YouTube or another platform: use RTMPS if the platform offers an address for it.
- OBS to a server over the public internet: use RTMPS if you can, or a protocol built for unreliable networks such as SRT.
- Encoder and server on the same trusted LAN: RTMP can be enough, as long as the network is really sealed off.
- Older encoder without RTMPS: use RTMP only up to an endpoint you control and secure the rest of the path.
- Mobile IRL uplink: on unstable cellular, SRT or SRTLA is usually more reliable. RTMPS fits after that, on the stable path from OBS to the platform.
TLS protects the connection from simple eavesdropping and from tampering in transit. It does not turn a compromised or published stream key into a safe one. So keep your stream key secret and replace it if you suspect a leak.
4. Keeping server URL, port, and stream key apart
Many errors come from mixing up the server address, the application path, and the stream key. The addresses and keys below are examples only, not targets to click or copy.
| Field | RTMP example | RTMPS example |
|---|---|---|
| Server | rtmp://stream.example:1935/live | rtmps://stream.example:443/live |
| Stream key | YOUR_SECRET_KEY | YOUR_SECRET_KEY |
| Full target path | rtmp://stream.example:1935/live/YOUR_SECRET_KEY | rtmps://stream.example:443/live/YOUR_SECRET_KEY |
5. Setting up RTMP or RTMPS in OBS
- In OBS, open Settings → Stream.
- If the platform is available as a ready-made service, pick it. A current platform preset is usually better than a server address you typed in by hand.
- For your own target, choose Custom and enter the full RTMP or RTMPS server address.
- Paste the stream key into its own field.
- With RTMPS, check that the server name matches the certificate. A raw IP address only works if the certificate is valid for exactly that.
- Test with a private or unlisted broadcast, and under View → Stats in OBS watch for dropped connections and dropped frames.
YouTube provides the RTMPS address in the Live Control Room and names port 443 as a possible explicit setting if you run into TLS problems. Official help: Encrypt your stream with RTMPS.
6. RTMPS on your own server
A classic Nginx RTMP server often listens unencrypted on TCP port 1935. Changing only the prefix of the encoder address from rtmp:// to rtmps:// is not enough. The server side has to actually accept TLS.
This is usually done with a TLS endpoint or a suitable proxy in front, which accepts RTMPS and forwards it internally to the RTMP service. You also need a domain, a valid certificate, the right firewall port, and automatic certificate renewal.
For a server that runs permanently, there is the detailed Linux guide with Nginx RTMP. If you want to run the receiving server and OBS on one Windows PC, use the separate Windows guide with NOALBS. A later RTMPS extension with a certificate and TLS proxy can build on the Linux setup.
7. A sensible setup for an IRL stream
RTMPS encrypts reliably, but it does not smooth out an unstable cellular connection. For a mobile stream, a combination often makes sense:
- Moblin, IRL Pro, or a mobile encoder sends over SRT or SRTLA to the relay or bonding server.
- OBS receives the mobile picture and adds scenes, alerts, audio, and outage protection.
- OBS sends the finished program stream over RTMPS to the target platform.
If you want to set up your own SRTLA receiver for mobile ingest, the automatic SRTLA installation guide walks you through it. It does not install an RTMP server; for that there is the separate RTMP server guide.
8. Common RTMP and RTMPS errors
| Symptom | Likely cause | Check |
|---|---|---|
| Connection refused right away | Wrong port, service not running, or firewall blocking | Check the server address and the specified TCP port |
| TLS or certificate error | Hostname doesn't match, certificate expired, or the server only speaks RTMP | Check the RTMPS address and certificate chain; don't just change the URL prefix |
| Authentication failed | Stream key wrong, expired, or entered in the wrong place | Copy the key again and watch for spaces |
| RTMP works, RTMPS doesn't | Encoder or server doesn't support RTMPS | Check current software, platform preset, and server configuration |
| Stream drops regularly on mobile | RTMP/RTMPS reacts badly to network switches and longer dropouts | Test SRT/SRTLA with a suitable latency for the mobile leg |
| Doubled or wrong URL | The stream key was appended to the URL and entered separately too | Follow the encoder's convention and keep the fields cleanly separate |
Technical background: RTMP carries audio, video, and metadata over a persistent connection; modern extensions are documented in the open E-RTMP project. Enhanced RTMP at Veovera.
Next steps
9. Common questions about RTMP and RTMPS
What is the difference between RTMP and RTMPS?
RTMP normally sends the live stream unencrypted. RTMPS wraps the same RTMP data stream in a TLS-encrypted connection, much like HTTP and HTTPS. That protects video, audio, and stream key better on the way to the server.
Is it enough to replace rtmp:// with rtmps:// in OBS?
No. The server has to actually accept TLS, with a valid certificate and a matching hostname. What that looks like on your own server is covered in the section RTMPS on your own server.
Does RTMPS make my stream key safe?
TLS protects the connection from simple eavesdropping and from tampering in transit. A published or compromised stream key is still not safe. Keep it secret and replace it if you suspect a leak.
Should I use RTMPS for mobile IRL streaming?
On the unstable cellular leg, SRT or SRTLA is usually more reliable. RTMPS fits after that, on the stable path from OBS to the target platform.
Which port goes with RTMP and RTMPS?
TCP 1935 is commonly used for RTMP and TCP 443 for RTMPS. Those are typical values, not a fixed rule. What counts is always the full address your server or platform gives you.