FLUX.3 Image

POST Base URL: https://api.hiapi.ai /v1/tasks

Image, video, and audio models are called through theUnified Async API POST /v1/tasks endpoint; only the input fields differ (see input parameters below).

Model summary

Model	flux-3-image
Type	Image generation and editing
Endpoint	POST /v1/tasks
Pricing	Live pricing

FLUX.3 Image API turns prompts and references into detailed visuals for products, spaces and creative work. Try online and view images, pricing and guides.

Request parameters

POST https://api.hiapi.ai/v1/tasks

# Create an async task — returns taskId immediately (generation runs async)
# Replace YOUR_API_KEY with your account API key
curl -X POST "https://api.hiapi.ai/v1/tasks" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "flux-3-image",
  "input": {
    "prompt": "A refined still life photograph of a miniature terracotta architectural model on ivory paper, a warm brass desk lamp, a sprig of olive leaves and a charcoal pencil, precise shadows and soft late-afternoon sunlight, restrained design-magazine composition, no text."
  }
}'

import requests, json

# Business params — fields vary by model (see the model page)
payload = json.loads(r'''
{
  "model": "flux-3-image",
  "input": {
    "prompt": "A refined still life photograph of a miniature terracotta architectural model on ivory paper, a warm brass desk lamp, a sprig of olive leaves and a charcoal pencil, precise shadows and soft late-afternoon sunlight, restrained design-magazine composition, no text."
  }
}
''')

# Create an async task — returns taskId immediately (generation runs async)
resp = requests.post(
    "https://api.hiapi.ai/v1/tasks",
    headers={"Authorization": "Bearer YOUR_API_KEY", "Content-Type": "application/json"},
    json=payload,
)
print(resp.json())  # Returns { code, message, data: { taskId } }

// Create an async task — returns taskId immediately (generation runs async)
// Replace YOUR_API_KEY with your account API key
const resp = await fetch("https://api.hiapi.ai/v1/tasks", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_API_KEY",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
  "model": "flux-3-image",
  "input": {
    "prompt": "A refined still life photograph of a miniature terracotta architectural model on ivory paper, a warm brass desk lamp, a sprig of olive leaves and a charcoal pencil, precise shadows and soft late-afternoon sunlight, restrained design-magazine composition, no text."
  }
}),
});
console.log(await resp.json()); // Returns { code, message, data: { taskId } }

model string required

Use flux-3-image.

example flux-3-image

input object required

Image creation parameters.

prompt string required

Describe the scene or the changes and details to preserve, up to 5000 characters

image_urls string[] optional

Provide 1–10 public HTTP(S) image URLs and assign each role in the prompt.

resolution enum optional

Choose an output pixel tier; exact dimensions depend on the aspect ratio

default 1K enum: 7681K1.5K2K4K

aspect_ratio enum optional

Choose output framing; auto uses the prompt and references. Select an explicit ratio for a fixed placement.

default auto enum: 21:92:116:93:27:54:35:41:14:53:4 +6

safety_tolerance integer optional

Content safety tolerance from 0–4; 0 is the strictest

default 2

grounding boolean optional

Allow web and image searches before generation to add visual context

default true

callback object optional

Receive a notification when the task completes or fails.

url string required

HTTPS address for task completion notifications.

example https://your-domain.com/hiapi/callback

when enum optional

Notify when the task reaches a final state.

default final enum: final

Example requests

Architectural miniature in late light

Terracotta, brass and paper form a restrained design still life; side light reveals shapes and materials.

Request body

{
  "model": "flux-3-image",
  "input": {
    "prompt": "A refined still life photograph of a miniature terracotta architectural model on ivory paper, a warm brass desk lamp, a sprig of olive leaves and a charcoal pencil, precise shadows and soft late-afternoon sunlight, restrained design-magazine composition, no text."
  }
}

Getting the result

Save data.taskId from the submission response.
Retrieve GET /v1/tasks/{taskId} until data.status is success or failed.
Read each image URL in data.output and save files you need before expireAt.

FAQ

Can one entry generate and edit?

Yes. Generate from text without references, or provide 1–10 images to edit around existing material.

How should I choose among the five tiers?

Start with 768 or 1K for a direction, consider 1.5K or 2K for more detail, and 4K when a larger file or cropping room is useful. Tiers do not specify fixed edges; inspect the returned dimensions.

How should I assign reference roles?

Assign the subject, setting and palette or style to specific references in order, including anything that should stay out.

How many images does each task return?

Each task returns one image. Adjust the brief and submit a separate task for another direction.

Can I choose the generated file format?

This entry has no file-format selector. Work with the returned file or convert it in an image tool after downloading.

When is search assistance useful?

Enable it when web or image searches could add visual context before generation. Turn it off for a direction based only on your own brief and references.

How should I keep images long term?

Generated image links have an expiry date. Download files you need to keep, or select permanent storage when creating the task. Existing images can also be re-stored by following the storage management guide.

Can I continue editing a result?

Save the result and supply it as a reference in a new task. Tasks are independent, so describe what to retain and what this revision should change.

How can I make lettering easier to inspect?

Put a short heading in quotes and describe its position, hierarchy and surrounding space. Check the lettering before use and finish typography in a design tool if needed.

When should I leave framing automatic?

Use automatic framing when the placement is flexible. Choose a ratio for a fixed banner, portrait poster or square card, then check the downloaded dimensions.

Where can I check the cost before generating?

Choose your parameters and check the Playground estimate and live pricing. Task records show the completed image and its charge.

Why can the same brief produce a different picture?

Composition and details can vary between results. Use a selected picture as a reference and specify preservation requirements when continuity matters.