I have run video through an upscaler frame by frame. On a still it looks clean. Put it in motion and the face starts to breathe, the grass crawls, the water falls apart into small squares. It flickers.
That is why this announcement took more of my time than yet another generator. Stable video upscaling is an old hole in the craft, and the few tools that plug it decently are closed and expensive.
Fact
The facts: on 20 August 2026 Black Forest Labs shipped FLUX Upscale - a standalone tool and an endpoint in its API which regenerates video at a higher resolution, up to native 4K. The input is from 480p up. The upscale_factor parameter takes 1.5x, 2x and 3x, which from an HD input gives roughly 1080p, 2K and 4K. It works in two modes: Precise at 4 steps, faster and cheaper, recommended when identity or reference detail has to be kept; and Creative at 8 steps, which pushes more correction and detail but can change or replace the identity. The prices are 0.07 dollars per megapixel-second for Precise and 0.10 dollars for Creative. Per BFL the tool understands the output of FLUX 3 natively and fixes things a general upscaler misses, such as blurred faces and grid artefacts on textures like water and grass. It is available through the API and the playground of BFL. There are no published benchmarks. Source: the Black Forest Labs blog, 20.08.2026.
The two modes say the most
Precise holds the face. Creative corrects it more aggressively and can hand you back a different person. That is not a small line in the documentation, it is the difference between a frame that goes into the edit and a frame that goes back for a reshoot.
The upscale here does not enlarge pixels. It regenerates the frame - and anything regenerated can decide the face looks different.
The price is by size and by time at once. Working from the announced numbers, one second in 4K on Precise comes to about 0.58 dollars, so a thirty-second clip is somewhere near 17 dollars before you have tried a second version. For an advert piece that is bearable. For an archive of old material the bill quickly becomes a different conversation.
And there are no weights. The company that made its name with open models is keeping the door shut this time - you go through their API or you do not go. It is logical, the tool is aimed at production, not at your laptop. But it also means one player sets the price.
There are no benchmarks either, so the check is one and it is yours. Take your own frame with water, grass or a face in motion, run it through both modes and watch it in motion, not on a still. That is where you see whether it flickers.
Official primary sources
Black Forest Labs - FLUX Upscale: 2K and 4K for Video (20.08.2026)BFL Docs - FLUX Video UpscaleThe visual is generated code-art, no third-party images.