How to use FLUX Video Upscale: the complete guide

How to use FLUX Video Upscale: the complete guide

Learn how to use FLUX Video Upscale on Morphic, step by step: upscaling a clip to 2x or 3x, reaching 4K, what creative mode changes, taking AI video to 4K, and the settings and limits.

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What FLUX Video Upscale does

FLUX Video Upscale is Black Forest Labs' video upscaler, built on FLUX 3. It enlarges a clip to 2x or 3x, up to 4K, and rebuilds the fine detail a plain resize cannot: skin, stubble, grain, fabric and foliage. The original audio carries through. BFL announced a full upgrade on October 23, 2026, and says the new version costs less than Topaz Astra 2 and runs about twice as fast.

Every frame in this guide comes from clips made with FLUX 3 Max on Morphic and upscaled with FLUX Video Upscale on Morphic. Each comparison shows the same crop at full size: the original enlarged with a standard resize, against the upscaled result.

The same boat hull upscaled 3x with FLUX Video Upscale, sharp wood grain, paint flakes and rivetsFLUX Video Upscale 3x
Weathered boat hull enlarged with a standard resize, soft wood grain and blurred paint flakesStandard resize

FLUX Video Upscale examples: what creative mode changes

BFL offers a precise mode that keeps the source as it is and a creative mode that rebuilds fine detail; Morphic runs creative. In order: a 360p market clip at 3x gains embroidery the small file never held; a stoneware bottle at 3x comes back sharper, with its speckles slightly redrawn, so check labels and logos; a portrait at 2x keeps the same face, with firmer wrinkles and stubble.

The same cushions upscaled 3x, embroidery and stitching in clear detailFLUX 3x
Embroidered cushions at a lantern-lit market from a 360p copy, blurry360p
The same bottle upscaled 3x, a crisper and slightly redrawn speckle patternFLUX 3x
Speckled stoneware bottle under a brass cap, enlarged with a standard resizeResized
The same man upscaled 2x, sharper wrinkles and stubbleFLUX 2x
Smiling older man by a harbour, enlarged with a standard resize, soft skin and beardResized

2x or 3x: how to pick the scale

The scale multiplies your source, so the source decides where you land. Output tops out at 4K, and anything larger is over the size limit.

SourceAt 2xAt 3x
360p720p1080p
720p1440p (2K)2160p (4K)
1080p2160p (4K)Over the size limit
1440pOver the size limitOver the size limit

For a 720p generation, 3x is the one-step route to 4K and 2x is a lighter step to 2K. For a 1080p master, 2x gets you to 4K. The two clips below are the same aerial shot from a 720p source, at 2x and at 3x, each cropped at full size: standard resize on the left, FLUX Video Upscale on the right.

2x: 720p to 1440p

3x: 720p to 4K

How to upscale a video with FLUX Video Upscale, step by step

  1. A video clip selected on the Morphic canvas, outlined in blue
    01

    Select the clip

    Put a generated or uploaded clip on the canvas and click it. MP4, up to 20 seconds and 50 MB.

  2. The Upscale section in the Details panel, with Model, Density and Frame rate fields and an Upscale button
    02

    Open Upscale

    In the Details panel on the right, open the Upscale section.

  3. The upscale model list with Flux Video selected
    03

    Choose Flux Video

    Pick Flux Video in the Model list. Topaz and Crystal sit beside it.

  4. The Density list with 2x and 3x, and 3x selected
    04

    Pick 2x or 3x

    Density is the scale: 3x takes 720p to 4K, 2x takes 1080p to 4K.

  5. The Upscale section set to Flux Video at 3x, with the cursor on the Upscale button
    05

    Click Upscale

    The upscaled clip lands next to the original, with the audio intact.

  6. A boat hull at full size: a soft standard resize on the left, the sharper upscale on the right
    06

    Compare the result

    Zoom into faces, labels and fine patterns before you publish.

Prefer the chat? Ask Copilot, for example: upscale this clip 3x with Flux Video.

How to upscale AI-generated video to 4K

Most video models render at 720p or 1080p, so 4K delivery is a second step. Generate the shot first, settle the action and the sound, then upscale only the take you keep.

  1. Generate at 720p or 1080p with any video model on Morphic, such as FLUX 3 Max or FLUX 3.
  2. Keep the clip to 20 seconds or less. Split a longer edit into parts and upscale each.
  3. Upscale with Flux Video: 3x from 720p, 2x from 1080p.
  4. Check faces and fine patterns, then export or place the clip in your edit.

A 720p FLUX 3 Max clip taken to 4K at 3x: standard resize on the left, FLUX Video Upscale on the right

FLUX Video Upscale settings and limits

  • Scale: 2x or 3x, chosen per clip.
  • Output: up to 4K.
  • Input: MP4, up to 20 seconds and 50 MB. BFL lists 2560 x 1440 as the largest input it accepts.
  • Audio: the original track is kept.
  • Mode: creative on Morphic.
  • Where: the Upscale panel on the canvas, or Copilot in the chat.
  • Plans: paid plans. The cost depends on clip length and output resolution; see pricing.

FAQs

Does FLUX Video Upscale work on footage that was not made with AI?

Yes. Black Forest Labs says it can upscale any video. Upload your own MP4 to Morphic and upscale it the same way as a generated clip.

Does FLUX Video Upscale keep the audio?

Yes. The original track carries through. Our 2x test clip with a spoken line came back with the line still in sync.

Why does a detail look slightly different after upscaling?

Morphic runs FLUX Video Upscale in creative mode, which rebuilds fine detail and can redraw small things such as a printed pattern. Check faces, labels and logos closely, and keep the original if a detail must stay exact.

Can I upscale a clip longer than 20 seconds?

Not in one pass. Split the clip into parts of 20 seconds or less, upscale each, and join them in your edit.

Should I use 2x or 3x?

Let the source decide. 3x takes a 720p clip to 4K; 2x takes a 1080p clip to 4K, or a 720p clip to 2K. Output tops out at 4K, and anything larger is over the size limit.

Which plan do I need for FLUX Video Upscale?

FLUX Video Upscale is available on Morphic's paid plans. The cost depends on the length of the clip and the output resolution; the pricing page has the current plans.