Blackforestlabs FLUX 3 Max Keyframes To Video API | Pricing & Docs

blackforestlabs/flux-3-max/keyframes-to-video

FLUX 3 Max Keyframes To Video builds a clip from stills locked to frame numbers, with optional audio at 720p or 1080p.

1. Get started

Use RunComfy's API to run blackforestlabs/flux-3-max/keyframes-to-video. For accepted inputs and outputs, see the model's schema.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/models/blackforestlabs/flux-3-max/keyframes-to-video \
  --header "Content-Type: application/json" \
  --header "Authorization: Bearer <token>" \
  --data '{
    "prompt": "He sets the robe on the rock, lowers himself into the steaming pool, then turns toward the woman beside him and smiles. Snow keeps falling. Water, soft wind, and a quiet laugh. No text.",
    "keyframes": [
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-1.webp",
        "frame_index": 0
      },
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-2.webp",
        "frame_index": 60
      },
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-3.webp",
        "frame_index": 120
      }
    ]
  }'

2. Authentication

Set the YOUR_API_TOKEN environment variable with your API key (manage keys in your Profile) and include it on every request as a Bearer token via the Authorization header: Authorization: Bearer $YOUR_API_TOKEN.

3. API reference

Submit a request

Submit an asynchronous generation job and immediately receive a request_id plus URLs to check status, fetch results, and cancel.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/models/blackforestlabs/flux-3-max/keyframes-to-video \
  --header "Content-Type: application/json" \
  --header "Authorization: Bearer <token>" \
  --data '{
    "prompt": "He sets the robe on the rock, lowers himself into the steaming pool, then turns toward the woman beside him and smiles. Snow keeps falling. Water, soft wind, and a quiet laugh. No text.",
    "keyframes": [
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-1.webp",
        "frame_index": 0
      },
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-2.webp",
        "frame_index": 60
      },
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-3.webp",
        "frame_index": 120
      }
    ]
  }'

Monitor request status

Fetch the current state for a request_id ("in_queue", "in_progress", "completed", or "cancelled").

curl --request GET \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/status \
  --header "Authorization: Bearer <token>"

Retrieve request results

Retrieve the final outputs and metadata for the given request_id; if the job is not complete, the response returns the current state so you can continue polling.

curl --request GET \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/result \
  --header "Authorization: Bearer <token>"

Cancel a request

Cancel a queued job by request_id; in-progress jobs cannot be cancelled.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/cancel \
  --header "Authorization: Bearer <token>"

4. File inputs

Hosted file (URL)

Provide a publicly reachable HTTPS URL. Ensure the host allows server-side fetches (no login/cookies required) and isn't rate-limited or blocking bots. Recommended limits: images ≤ 50 MB (~4K), videos ≤ 100 MB (~2–5 min @ 720p). Prefer stable or pre-signed URLs for private assets.

5. Schema

Input schema

{
  "type": "object",
  "title": "Input schema",
  "required": [
    "prompt",
    "keyframes"
  ],
  "properties": {
    "prompt": {
      "title": "Prompt",
      "description": "Describe how the clip should move between the keyframe stills.",
      "type": "string",
      "default": "He sets the robe on the rock, lowers himself into the steaming pool, then turns toward the woman beside him and smiles. Snow keeps falling. Water, soft wind, and a quiet laugh. No text."
    },
    "keyframes": {
      "title": "Keyframes",
      "description": "Up to 10 images. Each needs a unique frame_index on a 24 fps timeline, at most duration times 24.",
      "type": "array",
      "default": [
        {
          "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-1.webp",
          "frame_index": 0
        },
        {
          "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-2.webp",
          "frame_index": 60
        },
        {
          "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-3.webp",
          "frame_index": 120
        }
      ],
      "items": {
        "image_url": {
          "title": "Image URL",
          "description": "Keyframe image URL. PNG, JPEG, or WebP.",
          "type": "string",
          "format": "image_uri",
          "default": ""
        },
        "frame_index": {
          "title": "Frame Index",
          "description": "Position on the 24 fps timeline. Must be unique and at most duration times 24.",
          "type": "integer",
          "format": "int_slider_with_range",
          "minimum": 0,
          "maximum": 480,
          "default": 0
        }
      },
      "maxItems": 10,
      "minItems": 1
    },
    "aspect_ratio": {
      "title": "Aspect Ratio",
      "description": "Output frame shape. auto follows the first image.",
      "type": "string",
      "enum": [
        "auto",
        "21:9",
        "2:1",
        "16:9",
        "4:3",
        "1:1",
        "3:4",
        "9:16"
      ],
      "default": "auto"
    },
    "resolution": {
      "title": "Resolution",
      "description": "Output resolution. 720p is the default. 1080p is the sharper option.",
      "type": "string",
      "enum": [
        "720p",
        "1080p"
      ],
      "default": "720p"
    },
    "duration": {
      "title": "Duration",
      "description": "Clip length in whole seconds.",
      "type": "integer",
      "enum": [
        5,
        6,
        7,
        8,
        9,
        10,
        11,
        12,
        13,
        14,
        15,
        16,
        17,
        18,
        19,
        20
      ],
      "default": 5
    },
    "generate_audio": {
      "title": "Generate Audio",
      "description": "Create an audio track with the video. Turn this off for a silent clip.",
      "type": "boolean",
      "default": true
    },
    "reasoning_level": {
      "title": "Reasoning Level",
      "description": "low returns sooner. high spends more time on the prompt and is slower.",
      "type": "string",
      "enum": [
        "low",
        "high"
      ],
      "default": "high"
    },
    "seed": {
      "title": "Seed",
      "description": "Optional. Leave empty and the model picks a random seed.",
      "type": "integer"
    }
  }
}

Output schema

{
  "output": {
    "type": "object",
    "properties": {
      "image": {
        "type": "string",
        "format": "uri",
        "description": "single image URL"
      },
      "video": {
        "type": "string",
        "format": "uri",
        "description": "single video URL"
      },
      "images": {
        "type": "array",
        "description": "multiple image URLs",
        "items": {
          "type": "string",
          "format": "uri"
        }
      },
      "videos": {
        "type": "array",
        "description": "multiple video URLs",
        "items": {
          "type": "string",
          "format": "uri"
        }
      }
    }
  }
}

RunComfy

RunComfy is the premier ComfyUI platform, offering ComfyUI online environment and services, along with ComfyUI workflows featuring stunning visuals. RunComfy also provides AI Models, enabling artists to harness the latest AI tools to create incredible art.

1. Get started

Use RunComfy's API to run blackforestlabs/flux-3-max/keyframes-to-video. For accepted inputs and outputs, see the model's schema.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/models/blackforestlabs/flux-3-max/keyframes-to-video \
  --header "Content-Type: application/json" \
  --header "Authorization: Bearer <token>" \
  --data '{
    "prompt": "He sets the robe on the rock, lowers himself into the steaming pool, then turns toward the woman beside him and smiles. Snow keeps falling. Water, soft wind, and a quiet laugh. No text.",
    "keyframes": [
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-1.webp",
        "frame_index": 0
      },
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-2.webp",
        "frame_index": 60
      },
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-3.webp",
        "frame_index": 120
      }
    ]
  }'

3. API reference

Submit a request

Submit an asynchronous generation job and immediately receive a request_id plus URLs to check status, fetch results, and cancel.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/models/blackforestlabs/flux-3-max/keyframes-to-video \
  --header "Content-Type: application/json" \
  --header "Authorization: Bearer <token>" \
  --data '{
    "prompt": "He sets the robe on the rock, lowers himself into the steaming pool, then turns toward the woman beside him and smiles. Snow keeps falling. Water, soft wind, and a quiet laugh. No text.",
    "keyframes": [
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-1.webp",
        "frame_index": 0
      },
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-2.webp",
        "frame_index": 60
      },
      {
        "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-3.webp",
        "frame_index": 120
      }
    ]
  }'

Monitor request status

Fetch the current state for a request_id ("in_queue", "in_progress", "completed", or "cancelled").

curl --request GET \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/status \
  --header "Authorization: Bearer <token>"

Retrieve request results

Retrieve the final outputs and metadata for the given request_id; if the job is not complete, the response returns the current state so you can continue polling.

curl --request GET \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/result \
  --header "Authorization: Bearer <token>"

Cancel a request

Cancel a queued job by request_id; in-progress jobs cannot be cancelled.

curl --request POST \
  --url https://model-api.runcomfy.net/v1/requests/{request_id}/cancel \
  --header "Authorization: Bearer <token>"

4. File inputs

Hosted file (URL)

5. Schema

Input schema

{
  "type": "object",
  "title": "Input schema",
  "required": [
    "prompt",
    "keyframes"
  ],
  "properties": {
    "prompt": {
      "title": "Prompt",
      "description": "Describe how the clip should move between the keyframe stills.",
      "type": "string",
      "default": "He sets the robe on the rock, lowers himself into the steaming pool, then turns toward the woman beside him and smiles. Snow keeps falling. Water, soft wind, and a quiet laugh. No text."
    },
    "keyframes": {
      "title": "Keyframes",
      "description": "Up to 10 images. Each needs a unique frame_index on a 24 fps timeline, at most duration times 24.",
      "type": "array",
      "default": [
        {
          "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-1.webp",
          "frame_index": 0
        },
        {
          "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-2.webp",
          "frame_index": 60
        },
        {
          "image_url": "https://playgrounds-storage-public.runcomfy.net/tools/7471/media-files/ref-promo-3.webp",
          "frame_index": 120
        }
      ],
      "items": {
        "image_url": {
          "title": "Image URL",
          "description": "Keyframe image URL. PNG, JPEG, or WebP.",
          "type": "string",
          "format": "image_uri",
          "default": ""
        },
        "frame_index": {
          "title": "Frame Index",
          "description": "Position on the 24 fps timeline. Must be unique and at most duration times 24.",
          "type": "integer",
          "format": "int_slider_with_range",
          "minimum": 0,
          "maximum": 480,
          "default": 0
        }
      },
      "maxItems": 10,
      "minItems": 1
    },
    "aspect_ratio": {
      "title": "Aspect Ratio",
      "description": "Output frame shape. auto follows the first image.",
      "type": "string",
      "enum": [
        "auto",
        "21:9",
        "2:1",
        "16:9",
        "4:3",
        "1:1",
        "3:4",
        "9:16"
      ],
      "default": "auto"
    },
    "resolution": {
      "title": "Resolution",
      "description": "Output resolution. 720p is the default. 1080p is the sharper option.",
      "type": "string",
      "enum": [
        "720p",
        "1080p"
      ],
      "default": "720p"
    },
    "duration": {
      "title": "Duration",
      "description": "Clip length in whole seconds.",
      "type": "integer",
      "enum": [
        5,
        6,
        7,
        8,
        9,
        10,
        11,
        12,
        13,
        14,
        15,
        16,
        17,
        18,
        19,
        20
      ],
      "default": 5
    },
    "generate_audio": {
      "title": "Generate Audio",
      "description": "Create an audio track with the video. Turn this off for a silent clip.",
      "type": "boolean",
      "default": true
    },
    "reasoning_level": {
      "title": "Reasoning Level",
      "description": "low returns sooner. high spends more time on the prompt and is slower.",
      "type": "string",
      "enum": [
        "low",
        "high"
      ],
      "default": "high"
    },
    "seed": {
      "title": "Seed",
      "description": "Optional. Leave empty and the model picks a random seed.",
      "type": "integer"
    }
  }
}

Output schema

{
  "output": {
    "type": "object",
    "properties": {
      "image": {
        "type": "string",
        "format": "uri",
        "description": "single image URL"
      },
      "video": {
        "type": "string",
        "format": "uri",
        "description": "single video URL"
      },
      "images": {
        "type": "array",
        "description": "multiple image URLs",
        "items": {
          "type": "string",
          "format": "uri"
        }
      },
      "videos": {
        "type": "array",
        "description": "multiple video URLs",
        "items": {
          "type": "string",
          "format": "uri"
        }
      }
    }
  }
}

FLUX 3 Max Keyframes To Video builds a clip from stills locked to frame numbers, with optional audio at 720p or 1080p.

Table of contents

1. Get started

2. Authentication

3. API reference

Submit a request

Monitor request status

Retrieve request results

Cancel a request

4. File inputs

Hosted file (URL)

5. Schema

Input schema

Output schema

FLUX 3 Max Keyframes To Video builds a clip from stills locked to frame numbers, with optional audio at 720p or 1080p.

Table of contents

1. Get started

2. Authentication

3. API reference

Submit a request

Monitor request status

Retrieve request results

Cancel a request

4. File inputs

Hosted file (URL)

5. Schema

Input schema

Output schema

FLUX 3 Max Keyframes To Video: Multi-Frame 720p and 1080p Clips on Models and API | RunComfy

FLUX 3 Max Keyframes To Video builds a clip from stills locked to frame numbers, with optional audio at 720p or 1080p.

Table of contents

1. Get started

2. Authentication

3. API reference

Submit a request

Monitor request status

Retrieve request results

Cancel a request

4. File inputs

Hosted file (URL)

5. Schema

Input schema

Output schema

FLUX 3 Max Keyframes To Video: Multi-Frame 720p and 1080p Clips on Models and API | RunComfy

FLUX 3 Max Keyframes To Video builds a clip from stills locked to frame numbers, with optional audio at 720p or 1080p.

Table of contents

1. Get started

2. Authentication

3. API reference

Submit a request

Monitor request status

Retrieve request results

Cancel a request

4. File inputs

Hosted file (URL)

5. Schema

Input schema

Output schema