Flux 3 Enhance: Draft-to-Full-Quality Video Model
What is Flux 3 Enhance?
Flux 3 Enhance is the finishing step of Black Forest Labs' FLUX 3 video pipeline. FLUX 3 is BFL's first natively multimodal model, generating video with synchronized audio from a single prompt. When you run FLUX 3 in draft mode, it returns a fast, low-cost preview plus a reusable draft cache. Flux 3 Enhance takes that cache and re-renders the exact same shot at full quality: same seed, prompt, duration, aspect ratio, and audio, with nothing re-interpreted. You pass the X-Draft-Cache-Url from the draft you approved, choose HD or Full HD, and receive a finished MP4 with sound.
Key Features
- •Deterministic enhance that reproduces the approved draft shot with no drift or re-interpretation.
- •HD or Full HD (1920x1088) output at 24 fps through the FLUX 3 video upsampler.
- •Native audio, including dialogue, sound effects, and ambience, carried straight from the draft.
- •One required input: paste the draft cache URL; resolution is the only optional control.
- •Synchronous API that returns the finished video directly, no polling code required.
Best Use Cases
Flux 3 Enhance fits an iterate-cheaply-then-commit workflow. Explore many prompt, camera, and timing variations as fast draft previews, approve the single take you want, and enhance only that shot to delivery quality. It is well suited to social clips, ads, product and explainer videos, music-video beats, and short cinematic sequences where you must ship the exact preview you signed off on rather than a fresh generation. In our testing, a five-second golden-hour drone shot of a red sailboat upscaled cleanly from a 1280x704 draft to a 1920x1088 final with audio and framing intact.
Prompt Tips and Output Quality
There is no prompt field on Flux 3 Enhance because the shot is fixed by the draft. Do your creative work upstream: lock the prompt, duration, and aspect ratio in the FLUX 3 draft step, review the preview, and enhance only when you are happy. Pick fhd for final delivery and hd for lighter, faster finals. Because the enhance is seed-locked to the draft, output preserves motion and composition exactly, and testing showed clean upscaling with no added artifacts.
FAQs
What is a draft cache? It is the encrypted X-Draft-Cache-Url bundle FLUX 3 returns with a draft generation. It stores the shot so the enhance can reproduce it exactly.
Does enhancing change my shot? No. The enhance re-renders the same seed and prompt, so composition, motion, and audio match the preview you approved.
HD or Full HD? Use fhd (1920x1088) for hero shots and final delivery, and hd for quicker, lighter output.
Does it keep the audio? Yes. Dialogue, effects, and ambience generated with the draft are carried into the full-quality render.
Where do I get the draft cache URL? From a FLUX 3 text-to-video generation run in draft mode, which returns the X-Draft-Cache-Url in its response.
What is the output format? A standard MP4 video with an AAC audio track at 24 fps.