ViewerVitals.tv Public playback diagnostics for Twitch streams

Developed by OPD Technologies

See the stream your viewers receive

Run a free 30-second test on any live Twitch channel. ViewerVitals measures the playback arriving in this browser and tells you, in plain terms, what to look at next.

No account needed. Nothing about your test is stored.

More Twitch tools

The stream test is the main event. These sit alongside it and use the same public Twitch data.

Account age checker

See when any public Twitch account was created, its broadcaster status, and whether it is live right now. No login.

Saved history Next

Log in with Twitch to keep your tests, name them by network, and watch a channel's delivery over 30 days.

Compare devices Next

Run the same test from a phone, a second computer and a moderator's connection, then see the three side by side.

Continuous monitor Later

Leave a dashboard open on a second screen during a broadcast and get told the moment delivery slips.

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What the test actually measures

Six readings, taken once a second for thirty seconds. Three come straight from the Twitch player. Three are ViewerVitals working out what they mean together.

Delay behind live

How far behind the broadcaster this playback is running. Two to four seconds is normal on low-latency mode; eight to fifteen is normal on standard latency. Delay does not make a stream look worse, but it does break the timing between chat and what is happening on screen.

Reported by the Twitch player

Dropped frames

Frames this browser received but could not paint. Almost always a sign that the viewing device is busy, not that the stream is faulty. A handful over thirty seconds is ordinary.

Reported by the Twitch player

Playback buffer

How many seconds of video the player is holding in reserve. A thin buffer is the warning sign that comes before visible buffering: everything looks fine until one interruption arrives with nothing to cover it.

Reported by the Twitch player

Smoothness calc

How close the frame rate stayed to its target, and how much it moved around. A rock-steady 29.97 scores better than a stream lurching between 42 and 59, because the lurching is what viewers see as stutter.

Calculated by ViewerVitals

Connection health calc

Delay, buffer and dropped frames combined into one number describing how the stream felt to receive, separately from how sharp it looked.

Calculated by ViewerVitals

Qualities offered calc

The full list of qualities Twitch is serving for that channel, with the one your browser chose highlighted. This is the reading that separates “the broadcast is low quality” from “your connection picked a low quality” — two completely different problems that every other test reports as one.

Read from the player, interpreted by ViewerVitals