Introducing Runway Gen 4.5

Runway's Gen-4.5 launch illustrates the difference between a video people prefer and a scene that behaves consistently. The company's December 2025 announcement reports first place on the Artificial Analysis text-to-video leaderboard at launch. It describes the ranking as blind head-to-head voting: viewers choose between clips without knowing which model produced them.

Runway also acknowledges effects occurring before their causes and objects disappearing between frames. A clip can win a viewer's preference while retaining those flaws. The reported ranking is therefore evidence about preference in that comparison; it does not establish reliable physical behavior, which Runway says matters for its work on world models.