FLUX.1 [dev]

IMAGEFeaturedbfl-flux-1-dev

FLUX.1 [dev] is a powerful, open-weight 12 billion parameter rectified flow transformer from Black Forest Labs suitable for commercial use on Layer. It is designed for artists, researchers, and developers, offering cutting-edge image quality and competitive prompt adherence that rivals closed-source alternatives. Because it’s trained using guidance distillation, this model provides an efficient foundation for creative workflows and scientific exploration in the AI art space.

POST

/v2/workspaces/{workspace_id}/base-models/bfl-flux-1-dev/inferences

curl --request POST \
  --url https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/bfl-flux-1-dev/inferences \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "prompt": "a knight standing in a snowy forest",
  "aspect_ratio": "SQUARE_1K",
  "quality": "HIGH",
  "transparency": false,
  "guidance_file_init_image": [
    {
      "url": "<file_url>"
    }
  ]
}'

import requests

url = "https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/bfl-flux-1-dev/inferences"

payload = {
    "prompt": "a knight standing in a snowy forest",
    "aspect_ratio": "SQUARE_1K",
    "quality": "HIGH",
    "transparency": False,
    "guidance_file_init_image": [{ "url": "<file_url>" }]
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())

const url = 'https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/bfl-flux-1-dev/inferences';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"prompt":"a knight standing in a snowy forest","aspect_ratio":"SQUARE_1K","quality":"HIGH","transparency":false,"guidance_file_init_image":[{"url":"<file_url>"}]}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}

package main

import (
  "fmt"
  "strings"
  "net/http"
  "io"
)

func main() {

  url := "https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/bfl-flux-1-dev/inferences"

  payload := strings.NewReader("{\n  \"prompt\": \"a knight standing in a snowy forest\",\n  \"aspect_ratio\": \"SQUARE_1K\",\n  \"quality\": \"HIGH\",\n  \"transparency\": false,\n  \"guidance_file_init_image\": [\n    {\n      \"url\": \"<file_url>\"\n    }\n  ]\n}")

  req, _ := http.NewRequest("POST", url, payload)

  req.Header.Add("Authorization", "Bearer <token>")
  req.Header.Add("Content-Type", "application/json")

  res, _ := http.DefaultClient.Do(req)

  defer res.Body.Close()
  body, _ := io.ReadAll(res.Body)

  fmt.Println(res)
  fmt.Println(string(body))

}

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/bfl-flux-1-dev/inferences",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'prompt' => 'a knight standing in a snowy forest',
    'aspect_ratio' => 'SQUARE_1K',
    'quality' => 'HIGH',
    'transparency' => null,
    'guidance_file_init_image' => [
        [
                'url' => '<file_url>'
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

OkHttpClient client = new OkHttpClient();

MediaType mediaType = MediaType.parse("application/json");
RequestBody body = RequestBody.create(mediaType, "{\n  \"prompt\": \"a knight standing in a snowy forest\",\n  \"aspect_ratio\": \"SQUARE_1K\",\n  \"quality\": \"HIGH\",\n  \"transparency\": false,\n  \"guidance_file_init_image\": [\n    {\n      \"url\": \"<file_url>\"\n    }\n  ]\n}");
Request request = new Request.Builder()
  .url("https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/bfl-flux-1-dev/inferences")
  .post(body)
  .addHeader("Authorization", "Bearer <token>")
  .addHeader("Content-Type", "application/json")
  .build();

Response response = client.newCall(request).execute();

require 'uri'
require 'net/http'

url = URI("https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/bfl-flux-1-dev/inferences")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"prompt\": \"a knight standing in a snowy forest\",\n  \"aspect_ratio\": \"SQUARE_1K\",\n  \"quality\": \"HIGH\",\n  \"transparency\": false,\n  \"guidance_file_init_image\": [\n    {\n      \"url\": \"<file_url>\"\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

var client = new RestClient("https://api.app.layer.ai/api/v2/workspaces/:workspace_id/base-models/bfl-flux-1-dev/inferences");
var request = new RestRequest("", Method.Post);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"prompt\": \"a knight standing in a snowy forest\",\n  \"aspect_ratio\": \"SQUARE_1K\",\n  \"quality\": \"HIGH\",\n  \"transparency\": false,\n  \"guidance_file_init_image\": [\n    {\n      \"url\": \"<file_url>\"\n    }\n  ]\n}", ParameterType.RequestBody);
var response = client.Execute(request);

Authorizations

bearerAuth
oauth2

Parameters

Path Parameters

workspace_id

required

Workspace Id

Id of the workspace that owns the resource.

string format: uuid

Id of the workspace that owns the resource.

Query Parameters

session_name

Session Name

Organize this run under a named session. A new session is created if none matches.

string

nullable

Organize this run under a named session. A new session is created if none matches.

Header Parameters

Idempotency-Key

string

<= 255 characters

Opaque key making a retry of this request return the first result. A 2xx response is replayed for 24 hours with Idempotent-Replayed: true. A 4xx releases the key. A 5xx, or a request still running, holds the key for 120 seconds, during which a retry gets 409; after that a retry executes again. The key covers the method, path, query, and byte-identical body it was first used with; reusing it for a different request is rejected with 422. Protection is best effort: if the key store is unavailable, or a record is lost early, a retry can execute again even after an earlier 409. See the Idempotency section of the API description.

Request Body^required

application/json

FLUX.1 [dev]

object

prompt

Prompt

Describe what to generate, or the change to make.

string

tileability

Tileable

Make the image repeat without a visible seam when tiled side by side.

Advanced field.

boolean

negative_prompt

Negative prompt

What to keep out of the result.

Advanced field.

string

projection

Projection

Equirectangular is a 2:1 360 degree skybox whose sides meet and whose poles are settled.

string

nullable

Allowed value: EQUIRECTANGULAR

projection_strength

Projection strength

How strongly the 360 projection is drawn. Lower keeps more of the model’s own look.

Advanced field.

number

default: 1 >= 0.5 <= 1.5 multiple of 0.05

aspect_ratio

Aspect ratio

The shape and size of the output.

string

default: SQUARE_1K

Allowed values: SQUARE_1K PORTRAIT_2_3_1K PORTRAIT_3_4_1K PORTRAIT_9_16_1K LANDSCAPE_3_2_1K LANDSCAPE_4_3_1K LANDSCAPE_16_9_1K SQUARE_2K PORTRAIT_2_3_2K PORTRAIT_3_4_2K PORTRAIT_9_16_2K LANDSCAPE_3_2_2K LANDSCAPE_4_3_2K LANDSCAPE_16_9_2K LANDSCAPE_2_1_1K LANDSCAPE_2_1_1.5K LANDSCAPE_2_1_2K

quality

Quality

Higher levels render more detail, and can take longer and cost more.

string

default: HIGH

Allowed values: MEDIUM HIGH

seed

Seed

The starting point for the model’s randomness. The same seed and settings give the same result.

Advanced field.

integer

nullable

guidance_scale

Guidance scale

How closely the result follows the prompt. Lower gives the model more freedom.

Advanced field.

number

default: 3.5 >= 1 <= 20 multiple of 0.5

inference_steps

Inference steps

How many refinement passes the model makes. More add detail and take longer.

Advanced field.

integer

default: 28 >= 1 <= 50 multiple of 1

base_shift

Base shift

Shifts sampling at small sizes. Higher favours overall composition over fine detail.

Advanced field.

number

default: 0.5 <= 2 multiple of 0.05

max_shift

Max shift

Shifts sampling at large sizes. Higher favours overall composition over fine detail.

Advanced field.

number

default: 1.15 <= 2 multiple of 0.05

transparency

Transparent background

Output the subject alone, with no backdrop behind it.

boolean

guidance_file_init_image

Source image

The image to modify

Array<object>

InferenceFormFileRef

A single guidance/reference file supplied to a reference_image_list field.

The slot’s guidance type is fixed by the field it’s attached to; the caller supplies the file (its URL, or the id of a file it can read) and, where the model supports per-file weighting, a weight.

object

url

required

Url

The file’s URL, or the id of a file in this workspace or a public file.

string

weight

Weight

number

nullable

guidance_file_ip_adapter

Image prompt

Transfers the overall look of this image

Advanced field.

Array<object>

InferenceFormFileRef

A single guidance/reference file supplied to a reference_image_list field.

object

url

required

Url

The file’s URL, or the id of a file in this workspace or a public file.

string

weight

Weight

number

nullable

guidance_file_pose

Pose

Copies the pose in this image

Advanced field.

Array<object>

InferenceFormFileRef

A single guidance/reference file supplied to a reference_image_list field.

object

url

required

Url

The file’s URL, or the id of a file in this workspace or a public file.

string

weight

Weight

number

nullable

guidance_file_depth

Depth map

Copies the depth layout of this image

Advanced field.

Array<object>

InferenceFormFileRef

A single guidance/reference file supplied to a reference_image_list field.

object

url

required

Url

The file’s URL, or the id of a file in this workspace or a public file.

string

weight

Weight

number

nullable

guidance_file_canny

Canny edge

Follows the hard edges in this image

Advanced field.

Array<object>

InferenceFormFileRef

A single guidance/reference file supplied to a reference_image_list field.

object

url

required

Url

The file’s URL, or the id of a file in this workspace or a public file.

string

weight

Weight

number

nullable

guidance_file_softedge_hed

Soft edge

Follows the soft edges in this image

Advanced field.

Array<object>

InferenceFormFileRef

A single guidance/reference file supplied to a reference_image_list field.

object

url

required

Url

The file’s URL, or the id of a file in this workspace or a public file.

string

weight

Weight

number

nullable

guidance_file_lineart

Line art

Follows the lines in this drawing

Advanced field.

Array<object>

InferenceFormFileRef

A single guidance/reference file supplied to a reference_image_list field.

object

url

required

Url

The file’s URL, or the id of a file in this workspace or a public file.

string

weight

Weight

number

nullable

output_fit

Output canvas

Trim the transparent margin, and place the image on a canvas of a fixed size.

object

trim

Trim

boolean

canvas

OutputFitCanvas

string

default: CONTENT

Allowed values: CONTENT FIXED

width

Width

integer

nullable >= 1 <= 4096

height

Height

integer

nullable >= 1 <= 4096

scale

OutputFitScale

How the drawing goes onto a fixed canvas. The names follow the workflow Resize node’s.

string

default: PLACE

Allowed values: PLACE SHRINK_AND_PAD FIT_AND_PAD FIT_AND_CROP STRETCH

anchor

OutputFitAnchor

The point of the drawing that lands on the same point of the canvas.

BASE is a game tile’s base: its anchor, the bottom centre of the cell it stands on, lands at the bottom centre of the canvas, so tiles of one grid stand on the same point whatever rises above them.

string

default: CENTER

Allowed values: TOP_LEFT TOP_CENTER TOP_RIGHT CENTER_LEFT CENTER CENTER_RIGHT BOTTOM_LEFT BOTTOM_CENTER BOTTOM_RIGHT BASE

padding

Padding

integer

0 <= 512

prompt_language

Prompt language

The language the prompt is written in, so it reaches the model as you meant it.

Advanced field.

string

nullable

Example

{
  "prompt": "a knight standing in a snowy forest",
  "aspect_ratio": "SQUARE_1K",
  "quality": "HIGH",
  "transparency": false,
  "guidance_file_init_image": [
    {
      "url": "<file_url>"
    }
  ]
}

Responses

202

Successful Response

application/json

ExecuteForgeOutput

object

inference_id

required

Inference Id

Unique identifier for this forge run.

string format: uuid

status

required

InferenceStatus

Current status: IN_PROGRESS.

string

Allowed values: in_progress complete failed cancelled deleted

estimated_price_creative_units

Estimated Price Creative Units

Estimated price in Creative Units.

number

nullable

poll_interval_seconds

required

Poll Interval Seconds

Suggested polling interval in seconds.

integer

created_at

required

Created At

Timestamp of when the run was created.

string format: date-time

session_id

Session Id

Session ID the run was added to, if a session was specified.

string format: uuid

nullable

normalized_parameters

Any of:

NormalizedInferenceParameters
null

NormalizedInferenceParameters

Inference parameters after model-specific normalization.

These reflect the actual values used for generation, including model defaults applied for any parameters not explicitly set.

object

width

Width

Resolved output width in pixels.

integer

nullable

height

Height

Resolved output height in pixels.

integer

nullable

batch_size

Batch Size

Number of outputs to generate.

integer

nullable

num_inference_steps

Num Inference Steps

Resolved number of diffusion steps.

integer

nullable

guidance_scale

Guidance Scale

Resolved guidance scale.

number

nullable

duration_seconds

Duration Seconds

Resolved output length in seconds — video duration or audio clip length.

number

nullable

fps

Fps

Resolved FPS.

integer

nullable

Example

{
  "status": "in_progress"
}

401

Unauthenticated — missing or invalid Bearer token.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

403

Forbidden — insufficient permissions, or the access token lacks the scope the operation requires.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

404

Resource not found.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

409

The outcome of the request with this Idempotency-Key is not known yet: it is still running, or it failed without a stored response. Retry after the number of seconds in Retry-After.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

422

Invalid input parameters, or an Idempotency-Key reused for a different request.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

429

Rate limited — retry after the number of seconds in Retry-After.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

500

Internal server error.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

FLUX.1 [dev]

Authorizations

Parameters

Path Parameters

Query Parameters

Header Parameters

Request Bodyrequired

Example

Responses

202

Example

401

Example

403

Example

404

Example

409

Example

422

Example

429

Example

500

Example

Request Body^required