FLUX.3 First Last Frame Draft by Black Forest Labs is the fast, low-cost preview mode for first-to-last-frame video: provide a start and end frame and generate a quick draft, with native synchronized audio, to preview the transition before committing. When a draft lands, re-render it at full quality on FLUX.3 First Last Frame to Video and it keeps the same subjects, composition and motion. Supports durations from 5 to 20 seconds in aspect ratios from 21:9 to 9:16. Ideal for iterating reveals, morphs and match cuts fast.