Flux 1 Schnell

bfl/flux-1/schnell

Flux 1 Schnell by BFL - generate stunning images from text prompts with state-of-the-art AI. Supports multiple aspect ratios, styles, and high-resolution output for creative and commercial use.

Base price
$0.003USD / run
Execution
async
Model type
image
Input fields
6
Production route

Try the model

Playground

Open playground
Input
The prompt to generate an image from.
The aspect ratio of the generated image. Allowed values: 21:9, 16:9, 3:2, 4:3, 5:4, 1:1, 4:5, 3:4, 2:3, 9:16.
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.
112
The number of inference steps to perform. Range: 1 to 12.
The format of the generated image. Allowed values: jpeg, png.
The same seed and the same prompt given to the same version of the model will output the same image every time.
OutputExample

Examples

Select an example to load its inputs and result into the playground.

Model card

Specifications

Pricing

Base price
$0.003 / 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-1/schnell
Execution
async
Base URL
https://api.sandbase.ai
API
Unified Run API
Endpoint
/v1/run

Human preference

Arena

Elo ratings from blind side-by-side votes, compared with other image and video models.

Rankings sourced from Artificial Analysis Arena

Leaderboard
Text to Image
Rank
#104 of 106
Elo
740 ±20
Gap to #1
−482

Text-to-image arena: people pick the better of two images generated from the same prompt, without seeing the model names.

  1. #97Phoenix 0.9 UltraLeonardo.Ai833±20
  2. #98Phoenix 1.0 FastLeonardo.Ai827±20
  3. #99SRPOTencent826±20
  4. #100FLUX.1 [dev]Black Forest Labs823±45
  5. #101FIBO LiteBria813±16
  6. #102HiDream-O1-Image-DevHiDreamOn SandBase810±20
  7. #103Luma Photon FlashLuma Labs769±23
  8. #104FLUX.1 [schnell]Black Forest LabsThis model740±20
  9. #105OmniGen V2VectorSpaceLab717±26
  10. #106BagelBytedance594±35

API README

Flux 1 Schnell

FLUX.1 [schnell] generates an image in 1–4 steps, the cheapest FLUX option for quick drafts.

Fields

FieldTypeDefaultNotes
promptstring, required—Text instruction.
aspect_ratio21:9 / 16:9 / 3:2 / 4:3 / 5:4 / 1:1 / 4:5 / 3:4 / 2:3 / 9:1616:9Output shape.
guidance_scalenumber 1–203.5How strictly to follow the prompt.
num_inference_stepsinteger 1–124More steps add detail and time.
output_formatjpeg / pngjpegOutput file format.
seedintegerrandomFix it to compare prompt changes.

Billing

$0.003 per image.

RequestPrice
One image$0.003

Failed runs are not charged.

Prompting

  • Keep prompts short and concrete.

Limits

  • One image per request.

Also on SandBase

Related: bfl/flux-2/klein/4b (newer, fast).

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-1/schnell
# 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 $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'SANDBASE_JSON'
{
  "model": "bfl/flux-1/schnell",
  "prompt": "Extreme close-up of a single tiger eye, direct frontal view. Detailed iris and pupil. Sharp focus on eye texture and color. Natural lighting to capture authentic eye shine and depth. The word \"FLUX\" is painted over it in big, white brush strokes with visible texture.",
  "aspect_ratio": "16:9",
  "output_format": "jpeg",
  "guidance_scale": 3.5,
  "num_inference_steps": 4
}
SANDBASE_JSON
)
run_id=$(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 image & video models
ModelTypeDefault priceReleased
Flux 1 SchnellThis model
BFL
Image$0.00 / runNov 25, 2024
BFLImage$0.05 / runOct 1, 2026
BFLImage$0.05 / runOct 1, 2026
BFLImage$0.02 / runJan 15, 2026
BFLImage$0.02 / runJan 15, 2026
BFLImage$0.01 / runJan 15, 2026

Questions

FAQ

How do I call BFL Flux 1 Schnell through SandBase?

Create a SandBase API key, then send requests with the model ID "bfl/flux-1/schnell" to Unified Run API (/v1/run) at https://api.sandbase.ai. The request examples on this page show the exact payload.

Do I need a separate BFL account?

No. One SandBase API key and balance gives you access to BFL Flux 1 Schnell and the other models in the catalog; you do not need to sign up with BFL separately.