Rtmp Test
An RTMP test confirms that a live encoder ingest endpoint (an rtmp:// or rtmps:// URL) is reachable and actually carrying a stream. A passing result means our server completed the RTMP handshake, the publish/play stream key resolved, and we read a valid video keyframe — you will see a codec (almost always h264), a resolution, a frame rate, and a measured bitrate. RTMP is the workhorse for pushing into Wowza, nginx-RTMP, SRS, YouTube, Twitch, and most CDN ingest, so this is the first thing to check when an encoder "says it is live" but nothing appears downstream.
Run the test
Paste your stream URL (or run the pre-filled example). StreamProbe probes it from our servers — reachability, codec, resolution, frame rate, and a live bitrate sample.
How to read your RTMP results
Connect time
RTMP runs over TCP on port 1935 by default. A connect time under ~150 ms from our servers is healthy; a much higher number (or a timeout) usually means a firewall is dropping 1935, the host is far away, or the ingest server is overloaded. RTMP cannot fall back to another port the way HTTP can, so a blocked 1935 is a hard failure.
Bitrate
RTMP carries a near-constant bitrate set by your encoder (CBR is standard for ingest). The measured bitrate should sit close to your configured target — e.g. ~3.0–3.5 Mbps for 1080p30 h264. A bitrate well below target, or one that sags over the sample window, points at upstream packet loss or an encoder that is dropping frames to keep up.
Codec & keyframes (GOP)
RTMP only reliably carries h264 video and AAC audio — if you see another codec, downstream players will reject the stream even though the test "passes". GOP / keyframe interval is a paid-monitoring metric, but as a rule RTMP ingest wants a 2-second keyframe interval; longer GOPs break low-latency HLS repackaging on the CDN side.
Live flag
A reachable RTMP URL with no flowing media (publisher disconnected, wrong stream key) connects but never yields a keyframe — StreamTest reports it as reachable-but-not-live rather than healthy. That distinction is the single most common "my stream is broken" cause.
Frequently asked questions
Why does my RTMP URL connect but show no stream?
The RTMP handshake on port 1935 succeeded, but no publisher is pushing media to that stream key (or the key is wrong). Confirm your encoder is actually live and that the stream key in the URL matches the one configured on the ingest server.
What port does RTMP use?
RTMP uses TCP port 1935 by default; RTMPS (RTMP over TLS) typically uses 443. If StreamTest reports a connection timeout, the most common cause is a firewall blocking 1935 between the encoder/our servers and the ingest host.
What bitrate should an RTMP stream have?
Match your encoder target: roughly 3–6 Mbps for 1080p, 1.5–4 Mbps for 720p, using constant bitrate (CBR). A measured value far below target, or one that drifts down during the sample, indicates upstream loss or an overloaded encoder.