FLUX.1 Kontext [dev]

Name: FLUX.1 Kontext [dev]
Author: BFL

bfl/flux-2/kontext/dev

Flux 2 Kontext Dev by BFL - AI-powered image editing, style transfer, and transformation. Edit photos with natural language instructions, remove backgrounds, change styles, and enhance images effortlessly.

Use in agent Get API key

Base price: $0.0013USD / run
Execution: async
Model type: image
Input fields: 7

Try the model

Playground

Open playground

Input

Prompt(string)

The prompt to edit the image.

Image URL or upload(string)

Upload

PNG, JPEG, WebP, or GIF · 20 MiB maximum

The URL of the image to edit. Max width: 14142px, Max height: 14142px, Timeout: 20s

This field is required.

Guidance scale (CFG)(number)

120

The CFG (Classifier Free Guidance) scale is a measure of how close you want the model to stick to your prompt when looking for a related image to show you. Range: 1 to 20.

Num Inference Steps(integer)

1050

The number of inference steps to perform. Range: 10 to 50.

Output Format(string)

Output format Allowed values: jpeg, png.

Resolution Mode(string)

Determines how the output resolution is set for image editing. - `auto`: The model selects an optimal resolution from a predefined set that best matches the input image's aspect ratio. This is the recommended setting for most use cases as it's what the model was trained on. - `match_input`: The model will attempt to use the same resolution as the input image. The resolution will be adjusted to be compatible with the model's requirements (e.g. dimensions must be multiples of 16 and within supported limits). Apart from these, a few aspect ratios are also supported. Allowed values: auto, match_input, 1:1, 16:9, 21:9, 3:2, 2:3, 4:5, 5:4, 3:4, 4:3, 9:16, 9:21.

Seed(integer)

The same seed and the same prompt given to the same version of the model will output the same image every time.

OutputReady

Your output will appear here

Complete the inputs, then click Run.

Specifications

Pricing

Base price: $0.0013 / run

Context & modalities

Input: Schema-defined
Output: image

Capabilities

Chat: Not supported
Vision: Not supported
Reasoning: Not supported
Structured output: Not supported
Function calling: Not supported
Audio input: Not supported

Access

Provider: BFL
Model ID: bfl/flux-2/kontext/dev
Execution: async
API: Unified Run API
Endpoint: /v1/run

API README

FLUX.1 Kontext [dev]

FLUX.1 Kontext [dev] edits and enhances photos from natural-language instructions. A required image supplies the visual foundation and a required prompt communicates the revision, creating a direct path from an existing asset to an updated one.

Guidance can be adjusted from 1 to 20 and inference steps from 10 to 50. The model also offers resolution modes including automatic, input-matched, square, landscape, and portrait choices, plus JPEG or PNG export and seed control.

Highlights

Photo-first revision. Begin with a required image so the edit remains connected to an existing asset.

Written creative direction. Use a required prompt to describe the change or enhancement in natural language.

Broad refinement controls. Tune guidance from 1–20 and inference steps from 10–50 for the intended generation pass.

Resolution and export choices. Select an automatic, input-matched, or fixed resolution mode, then export JPEG or PNG with an optional seed.

Pricing

Billing unit	Price
Per request	$0.00125

When to Use

✅ Good fit	❌ Consider alternatives
The model's named workflow matches the source material and intended output	A different input modality or model route is required
A managed asynchronous result is suitable for the production pipeline	A synchronous, interactive editor is essential
The documented controls cover the required duration, framing, or format	The project needs controls outside this endpoint's schema
Creative iteration benefits from a repeatable request structure	Exact deterministic pixels, frames, geometry, or samples are mandatory
A finished downloadable media asset is the desired deliverable	Editable source layers or a native project file are required

Prompt Guide

For image-conditioned generation, state the intended result first, then add the subject or source treatment, progression, style, and delivery constraints. Keep one creative variable per phrase, use the documented field names for controls, and change one setting at a time when comparing results.

{
  "image": "https://example.com/start-frame.png",
  "output_format": "jpeg",
  "prompt": "Change the setting to a day time, add a lot of people walking the sidewalk while maintaining the same style of the painting"
}

Technical Specs

Spec	Value
Model ID	`bfl/flux-2/kontext/dev`
Inputs	guidance_scale, image, num_inference_steps, output_format, prompt, resolution_mode, seed
Required inputs	prompt, image
Output fields	content_type, url
Execution	Async (submit, then poll for result)
Output Format	jpeg / png

Related Models

bfl/flux-2/kontext/max/multi — Compare this concrete local family route.
bfl/flux-2/kontext/max/text-to-image — Compare this concrete local family route.
bfl/flux-2/kontext/pro/multi — Compare this concrete local family route.

Start building

Send your first request

OpenAI-compatible endpoint with unified authentication and usage tracking.

Production API

Unified Run API endpoint

https://api.sandbase.ai/v1/run

Model ID

bfl/flux-2/kontext/dev

# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
  -X POST "https://api.sandbase.ai/v1/run" \
  -H "Authorization: Bearer $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'SANDBASE_JSON'
{
  "model": "bfl/flux-2/kontext/dev",
  "image": "https://static.sandbase.ai/examples/bfl/flux-2/kontext/dev/input_image_0.webp",
  "prompt": "Change the setting to a day time, add a lot of people walking the sidewalk while maintaining the same style of the painting",
  "output_format": "jpeg",
  "guidance_scale": 2.5,
  "resolution_mode": "match_input",
  "num_inference_steps": 28
}
SANDBASE_JSON
)
run_id=$(printf '%s' "$result" | jq -r .id)
for attempt in $(seq 1 120); do
  status=$(printf '%s' "$result" | jq -r .status)
  case "$status" in completed|failed|timeout) break ;; esac
  sleep 2
  result=$(curl --fail-with-body --silent \
    -H "Authorization: Bearer $SANDBASE_API_KEY" \
    "https://api.sandbase.ai/v1/run/$run_id")
done
status=$(printf '%s' "$result" | jq -r .status)
[ "$status" = completed ] || { echo "Generation ended: $status" >&2; exit 1; }
printf '%s\n' "$result"

Choose your model

Compare models

All language models

Model	Context	Input / 1M	Output / 1M	Released
FLUX.1 Kontext [dev]This model `BFL`	—	—	—	May 28, 2025
FLUX Virtual Try-On `BFL`	—	—	—	May 28, 2026
Flux Pro Erase `BFL`	—	—	—	May 21, 2026
Flux 2 Pro `BFL`	—	—	—	May 14, 2026
FLUX.2 [klein] 9B LoRA `BFL`	—	—	—	Mar 17, 2026
FLUX.2 [klein] 9B LoRA `BFL`	—	—	—	Mar 17, 2026