Image by Stable Diffusion

Stable Diffusion 3.5 Large API

Stability AI's highest-quality Stable Diffusion 3.5 model, an 8-billion-parameter MMDiT that excels at photorealism, typography, and prompt adherence.

Integrate Stable Diffusion 3.5 Large with a single API call — one key, one unified endpoint, and shared billing across every model on Apiframe.

model: "stable-diffusion-3.5-large"

What's special about Stable Diffusion 3.5 Large

Highest SD 3.5 quality

The 8B-parameter flagship tier for detailed, photorealistic images with strong prompt adherence.

Text and image to image

Start from a prompt, or pass an image URL for image-to-image with adjustable prompt_strength.

Flexible aspect ratios

Choose from nine aspect ratios plus cfg, steps, negative prompt, and output format controls.

Made with Stable Diffusion 3.5 Large

A few outputs generated through the Stable Diffusion 3.5 Large API on Apiframe.

Sample coming soon

A cinematic portrait of an astronaut in a neon-lit alley, 85mm, shallow depth of field

Sample coming soon

Cozy isometric coffee shop, warm morning light, highly detailed 3D render

Sample coming soon

A majestic snow leopard on a misty mountain ridge at golden hour

Overview

Endpoint
POST /v2/images/generate
Model ID
stable-diffusion-3.5-large
Params key
stableDiffusionParams
Modality
Image
Provider
Stable Diffusion
Avg. completion
~10s

Capabilities

Aspect ratios1:1, 16:9, 21:9, 3:2, 2:3, 4:5, 5:4, 9:16, 9:21
Image inputSupported
Avg. time~10s

Quick start

Send a single POST /v2/images/generate request with your API key to generate with Stable Diffusion 3.5 Large. The call returns a jobId you can poll or receive via webhook.

curl -X POST https://api.apiframe.ai/v2/images/generate \
  -H "X-API-Key: afk_your_api_key_here" \
  -H "Content-Type: application/json" \
  -d '{
        "prompt": "a sleek silver sports car on a coastal highway at sunset, hyper-realistic",
        "model": "stable-diffusion-3.5-large",
        "stableDiffusionParams": {
            "image": "https://example.com/input.jpg",
            "prompt_strength": 0.85,
            "negative_prompt": "What you do NOT want to see…",
            "cfg": 3.5
        }
    }'
import requests

response = requests.post(
    "https://api.apiframe.ai/v2/images/generate",
    headers={
        "X-API-Key": "afk_your_api_key_here",
        "Content-Type": "application/json",
    },
    json={
        "prompt": "a sleek silver sports car on a coastal highway at sunset, hyper-realistic",
        "model": "stable-diffusion-3.5-large",
        "stableDiffusionParams": {
            "image": "https://example.com/input.jpg",
            "prompt_strength": 0.85,
            "negative_prompt": "What you do NOT want to see…",
            "cfg": 3.5
        }
    },
)
print(response.json())  # { "jobId": "...", "status": "QUEUED" }
const response = await fetch("https://api.apiframe.ai/v2/images/generate", {
  method: "POST",
  headers: {
    "X-API-Key": "afk_your_api_key_here",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "prompt": "a sleek silver sports car on a coastal highway at sunset, hyper-realistic",
    "model": "stable-diffusion-3.5-large",
    "stableDiffusionParams": {
      "image": "https://example.com/input.jpg",
      "prompt_strength": 0.85,
      "negative_prompt": "What you do NOT want to see…",
      "cfg": 3.5
    }
  }),
});
const { jobId } = await response.json();
console.log(jobId);

Response & job lifecycle

Generation is asynchronous. A successful submission returns 202 Accepted with a jobId. Poll GET /v2/jobs/{id} (or supply a webhook_url) until the status is COMPLETED; the result field then holds the output URL(s).

1. Submission response (202)

{
  "jobId": "b2c3d4e5-f6a7-8901-bcde-f23456789012",
  "status": "QUEUED"
}

2. Poll for the result

curl https://api.apiframe.ai/v2/jobs/JOB_ID \
  -H "X-API-Key: afk_your_api_key_here"
import requests, time

while True:
    job = requests.get(
        "https://api.apiframe.ai/v2/jobs/JOB_ID",
        headers={"X-API-Key": "afk_your_api_key_here"},
    ).json()
    if job["status"] in ("COMPLETED", "FAILED"):
        break
    time.sleep(2)
print(job["result"])
let job;
do {
  await new Promise((r) => setTimeout(r, 2000));
  job = await fetch("https://api.apiframe.ai/v2/jobs/JOB_ID", {
    headers: { "X-API-Key": "afk_your_api_key_here" },
  }).then((r) => r.json());
} while (job.status !== "COMPLETED" && job.status !== "FAILED");
console.log(job.result);

Input schema

Request parameters accepted by the Stable Diffusion 3.5 Large endpoint. Model-specific options are nested under the params object shown below.

Parameter Type Required Default Allowed / range Description
prompt string required Text description of what to generate.
model string required "stable-diffusion-3.5-large" "stable-diffusion-3.5-large" The model identifier for this endpoint.
stableDiffusionParams.image string (URL) optional Optional image for image-to-image mode. Output matches its aspect ratio.
stableDiffusionParams.prompt_strength number optional 0.85 min 0, max 1, step 0.05 Denoising strength for image-to-image (0–1). 1.0 ignores the input image.
stableDiffusionParams.negative_prompt string optional Negative prompt
stableDiffusionParams.cfg number optional 3.5 min 0, max 20, step 0.1 How strictly to follow the prompt.
stableDiffusionParams.steps number optional 28 min 1, max 40, step 1 Steps
stableDiffusionParams.output_format string optional "webp" "webp", "jpg", "png" Output format
stableDiffusionParams.output_quality number optional 90 min 0, max 100, step 1 Output quality
stableDiffusionParams.seed number optional step 1 Reuse a number to reproduce the same result.

Frequently Asked Questions

Common questions about the Stable Diffusion 3.5 Large API.

What does Stable Diffusion 3.5 Large cost?

Pricing is flat: 12 credits per generated image, regardless of aspect ratio or steps.

How do I do image-to-image?

Pass stableDiffusionParams.image with an image URL. The output adopts that image’s aspect ratio, and prompt_strength (0–1) controls how much of the original is preserved.

Still have questions?

Start building with the Stable Diffusion 3.5 Large API

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