POST/reroll4 creditsMidjourney only

Reroll

Re-run a generation with the same or tweaked prompt, producing an entirely new 2×2 grid. Use this when none of the four grid images are heading in the right direction and you want completely fresh results. Unlike /variations, reroll gives Midjourney a blank slate — the output will not resemble the original grid. Midjourney only.

Request Parameters

Parameter	Type	Required	Description
parent_task_id	`string`	Required	Task ID of the original /imagine task to reroll.
prompt	`string`	Optional	Optional modified prompt. If omitted, the original prompt is reused.
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

curl -X POST https://api.journeyapi.com/api/v1/reroll \
  -H "Authorization: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "parent_task_id": "550e8400-e29b-41d4-a716-446655440000",
    "webhook_url": "https://your-server.com/webhook"
  }'

Immediate Response

Returns immediately with a task ID. Use /fetch or webhooks to get the result.

200 OK

{
  "task_id": "661f9511-f30c-52e5-b827-557766551111"
}

Response Fields

Field	Type	Description
task_id	`string`	UUID of the new reroll task.
task_type	`string`	Always "reroll".
original_image_url	`string`	URL of the new 2×2 grid image.
image_urls	`string[]`	Array of 4 individual image URLs.

Tips

1Rerolling is equivalent to hitting the 🔄 button in the Midjourney Discord.
2You can optionally modify the prompt to get variations on a theme.

Quirks & Gotchas

The parent_task_id must reference a completed /imagine task. Rerolling an upscale or variation will return a 400 error.

Expert Tips & Best Practices

Reroll vs. Variations — when to use each

Reroll is a hard reset: Midjourney ignores the previous grid entirely and generates fresh candidates. Use it when the composition, style, or subject is wrong. Variations (positional, index 1–4) stay closer to a specific grid image's direction. Use variations when one image has the right feel but needs refinement.

Prompt tweaking strategy

When rerolling with a modified prompt, change only one element at a time so you can isolate what's driving the output. Add or remove a single descriptor, adjust --chaos, or swap the style reference. If you change too many things at once, you won't know what drove the improvement.

Related Endpoints

POST/imagine POST/variations