Midjourney Enhance replaces Upscale: the Sume image upscale API

Midjourney's 9/16/26 changelog says that in the v8.2 editor the Enhance feature replaces the previous Upscale button. If you are looking for the same job from code, Sume has a separate image upscale route that takes an existing image URL and an upscale_factor from 1 to 4. It enlarges a still you already have; it is not a generator.

What changed at Midjourney

Midjourney's own wording.

The Sume upscale route

The route is POST /v1/image-upscale-1.0/upscale, public model id sume/image-upscale-1.0. The required field is a public HTTPS image_url. Optional fields are upscale_factor (1 to 4, default 2) and output_format (png, jpg or webp, default png). Sume picks the upscaler server-side and you do not send provider ids.

On main, the tool description for upscaling quotes roughly $0.0044 per image after margin. Treat that as an estimate and read live pricing in the catalog before a large batch.

curl -X POST "https://api.sume.com/v1/image-upscale-1.0/upscale" \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: upscale-hero-001" \
  -d '{
    "image_url": "https://example.com/hero.png",
    "upscale_factor": 2,
    "output_format": "png"
  }'

Then collect the result

Submit returns a job; poll GET /v1/jobs/{id}/status and read GET /v1/jobs/{id}/result when it completes. The result lists artifacts with Sume-hosted media.sume.com URLs. See Jobs and results.

Reuse the same Idempotency-Key only for the same operation and payload when retrying after a timeout.

Upscale is not a rerender

Enhance in Midjourney may do more than enlarge; Sume's route is named an upscaler, so expect a larger version of the same image rather than a new interpretation. If you want a new interpretation at higher quality, generate again with a higher quality on a model that lists it.

Do not regenerate a picture just to make it bigger. Upscale it.

Order of operations

When a pipeline needs more than one step:

• Generate, then upscale.
• Remove the background before or after? See the related post on order.
• Keep the original URL so you can redo a step without paying for the first.

Picking a factor

The documented range is 1 to 4 with a default of 2. A 2x pass is the usual first choice for print-ready crops and retina web images. Go higher only when the end use needs it, since larger outputs cost more bytes and more time to move around.

If you need an exact pixel size rather than a factor, upscale to the next factor that covers it and resize down in your own pipeline. The related posts on exact pixel sizes cover that approach.

Choose output_format for the destination: png for lossless masters, webp or jpg for delivery. Keep the master and derive delivery files from it so you only upscale once.