/upscale-2x-4x2 creditsMidjourney onlyUpscale 2x / 4x
Multiply an image's pixel dimensions by 2x or 4x using AI upscaling. Can take either a prior JourneyAPI task as parent or any arbitrary public image URL, making this useful for upscaling images from outside JourneyAPI entirely. Use 4x when preparing artwork for large-format printing where you need to hit 300 DPI at the final print size. Midjourney only when using parent_task_id.
Request Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
| parent_task_id | string | Conditional | Task ID of a prior task. Either this OR image_url is required. |
| image_url | string | Conditional | URL of any image to upscale. Either this OR parent_task_id is required. |
| type | string | Required | Upscale multiplier.2x4x |
| index | string | Optional | If parent is a grid, which image to upscale.1234 |
| webhook_url | string | Optional | URL where we POST the completed task result. |
| webhook_secret | string | Optional | Sent as x-webhook-secret header in webhook delivery. |
Example Request
curl -X POST https://api.journeyapi.com/api/v1/upscale-2x-4x \
-H "Authorization: YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"image_url": "https://example.com/my-image.png",
"type": "2x",
"webhook_url": "https://your-server.com/webhook"
}'Immediate Response
Returns immediately with a task ID. Use /fetch or webhooks to get the result.
{
"task_id": "994c2844-c63f-85h8-e150-880099884444"
}Response Fields
| Field | Type | Description |
|---|---|---|
| task_id | string | UUID of the upscale task. |
| task_type | string | "upscale-2x" or "upscale-4x". |
| image_url | string | URL of the upscaled image. |
Tips
- 1You can upscale any publicly accessible image — it doesn't have to come from a previous JourneyAPI task.
- 24x upscale produces very large images and takes longer to process.
- 3If upscaling from a grid, pass the index to select which image.
Quirks & Gotchas
You must provide exactly one of parent_task_id or image_url, not both.
When using image_url, the image must be publicly accessible (no auth-gated URLs).
Expert Tips & Best Practices
When to use 4x (print resolution math)
A standard Midjourney 1x upscale outputs around 1024px on the short side. At 4x that becomes ~4096px. For a 300 DPI print, divide pixels by 300 to get max print inches: 4096 / 300 ≈ 13.6". So 4x is appropriate for prints up to ~A3/tabloid. For larger formats (posters, banners), you need a dedicated large-format upscaler. For web or social media, 2x is always sufficient.
Upscaling arbitrary images
Because you can pass any image_url, this endpoint works as a general-purpose AI upscaler for images not generated by JourneyAPI. This is useful when you want to upscale reference images, user-uploaded photos, or images from other AI tools before using them as inputs to /blend or /imagine.