A technique that dynamically adjusts video quality during playback based on the viewer's network conditions.
Adaptive bitrate streaming (ABR) is a method of delivering video where the player automatically switches between different quality levels during playback based on the viewer's available bandwidth and device capabilities. It is like a road navigation system that reroutes you to smaller roads when the highway is congested — you keep moving forward, just at a different speed, rather than sitting in traffic.
ABR requires the video to be transcoded into multiple renditions at different quality levels — for example, 360p, 720p, and 1080p. Each rendition is split into small segments (a few seconds each), and a manifest file describes all available options.
During playback, the player continuously measures download speed. If a 1080p segment takes too long to download, the player switches to 720p for the next segment. If bandwidth improves, it steps back up. This switching happens seamlessly — viewers typically do not notice the quality change because it occurs between segments.
The two dominant protocols for ABR are HLS (HTTP Live Streaming) and MPEG-DASH. Both follow the same principle of segmented delivery with a manifest file, though they differ in implementation details. HLS has the broadest device support and is the de facto standard for web video.
Without ABR, you face an impossible choice: serve high quality and accept that viewers on slower connections will buffer constantly, or serve low quality and waste the potential of viewers with fast connections. ABR eliminates this tradeoff by serving the right quality to each viewer automatically.
The business impact is direct. Studies consistently show that buffering is the number one cause of viewers abandoning video. ABR dramatically reduces buffering events, which means higher completion rates, longer watch times, and better engagement with your content.
Every video uploaded to host.video is automatically transcoded into multiple HLS quality levels for adaptive bitrate delivery. The player handles all ABR logic client-side, switching quality seamlessly based on each viewer's connection.