What is FAST channels?

FAST stands for free ad-supported streaming TV. Like broadcast TV, a FAST channel runs a schedule of programmes, and viewers tune in rather than pick each title. Like other streaming, it arrives over the internet, often on connected TVs. Viewers pay nothing, so ads fund the service, and FAST channels are a growing source of CTV inventory.

The ads work like other CTV ads. They play in breaks of several ads, called ad pods, and are usually stitched into the stream with server-side ad insertion so the channel keeps playing smoothly. Each ad still comes from a VAST response, and the stitching server must pass each viewer’s device IP and user agent so buyers can trust the impressions.

Like any CTV inventory, FAST breaks can reach buyers through more than one seller, such as the channel owner and a TV platform that holds a share of the breaks. Listing every seller in app-ads.txt, or declaring partners with inventorypartnerdomain, keeps those breaks verifiable.