Name: Realistic Vision v5.1 API: Photorealistic Text to Image
Brand: magicapi
SKU: api-magicapi-realistic-image-generation-lucataco-realistic-vision-v5-1
Availability: InStock
Author: API Market

Shashank Agarwal

# 📷 Photorealistic Text-to-Image Generator API (SG161222 Realistic Vision v5.1)

## Overview
Realistic Vision v5.1 is a photorealistic image model published by SG161222. This listing runs an implementation of Realistic Vision v5.1 with VAE by lucataco. It generates one image from a text prompt, with a long default negative prompt that steers results away from cartoon, render and distorted-anatomy looks.

Send a `prompt` (photography terms such as "RAW photo", "film grain" or a camera name are used in the default and example prompts), and optionally set the size up to 1920 x 1920 pixels, the number of `steps`, the `guidance` scale and the `scheduler`. Each request returns the URL of one image.

## Features
- **Photorealistic output**: built for realistic photos such as portraits.
- **Default negative prompt**: a detailed negative prompt is applied unless you send your own.
- **Custom size**: `width` and `height` from 0 to 1920 pixels (default 512 x 728).
- **Sampling controls**: `steps` (0 to 100, default 20), `guidance` (default 5, 3.5 to 7 recommended) and the `EulerA` or `MultistepDPM-Solver` scheduler.
- **Reproducible results**: set `seed` to a fixed value; `0` (default) picks a random seed.

## Use Cases
1. **Portrait photography**: generate realistic portraits for mockups, presentations and creative projects.
2. **Stock-style images**: create realistic scenes of people and places for blogs and marketing pages.
3. **Concept references**: produce photo-like references for characters, clothing or lighting.
4. **Prototyping**: fill app and website prototypes with realistic placeholder photos.

## Visual Examples
### Example Input
Prompt: "RAW photo, a portrait photo of a latina woman in casual clothes, natural skin, 8k uhd, high quality, film grain, Fujifilm XT3", 512 x 728 pixels, 20 steps, guidance 5, seed 1339:

```json
{
  "seed": 1339,
  "steps": 20,
  "width": 512,
  "height": 728,
  "prompt": "RAW photo, a portrait photo of a latina woman in casual clothes, natural skin, 8k uhd, high quality, film grain, Fujifilm XT3",
  "guidance": 5,
  "scheduler": "EulerA",
  "negative_prompt": "(deformed iris, deformed pupils, semi-realistic, cgi, 3d, render, sketch, cartoon, drawing, anime:1.4), text, close up, cropped, out of frame, worst quality, low quality, jpeg artifacts, ugly, duplicate, morbid, mutilated, extra fingers, mutated hands, poorly drawn hands, poorly drawn face, mutation, deformed, blurry, dehydrated, bad anatomy, bad proportions, extra limbs, cloned face, disfigured, gross proportions, malformed limbs, missing arms, missing legs, extra arms, extra legs, fused fingers, too many fingers, long neck"
}
```

### Example Output
![Photorealistic portrait generated by the Realistic Vision v5.1 API](https://blog.api.market/wp-content/uploads/2026/10/realistic-vision-v5-1-output-4ba9psyn-api-market-1.png)

## Input Parameters
| Field | Type | Required | Default | Allowed values | Description |
| --- | --- | --- | --- | --- | --- |
| `prompt` | string | No | `RAW photo, a portrait photo of a latina woman in casual clothes, natural skin, 8k uhd, high quality, film grain, Fujifilm XT3` |  | Text prompt describing the image |
| `negative_prompt` | string | No | `(deformed iris, deformed pupils, semi-realistic, cgi, 3d, render, sketch, cartoon, drawing, anime:1.4), text, close up, cropped, out of frame, worst quality, low quality, jpeg artifacts, ugly, duplicate, morbid, mutilated, extra fingers, mutated hands, poorly drawn hands, poorly drawn face, mutation, deformed, blurry, dehydrated, bad anatomy, bad proportions, extra limbs, cloned face, disfigured, gross proportions, malformed limbs, missing arms, missing legs, extra arms, extra legs, fused fingers, too many fingers, long neck` |  | Things to avoid in the image |
| `steps` | integer | No | `20` | 0 to 100 | Number of inference steps |
| `guidance` | number | No | `5` |  | Guidance scale (3.5 to 7 recommended) |
| `scheduler` | string | No | `EulerA` | `EulerA`, `MultistepDPM-Solver` | Scheduler |
| `width` | integer | No | `512` | 0 to 1920 | Width of the image in pixels |
| `height` | integer | No | `728` | 0 to 1920 | Height of the image in pixels |
| `seed` | integer | No | `0` |  | Random seed (0 = random, maximum 2147483647) |

## Pricing
- **Pay As You Go (PAYG) pricing**: you only pay for what you use.
- **Price**: $0.012 per API unit.
- **1 API unit = 1 successful request that finishes within 11 seconds of processing.** A request that takes longer is billed 1 unit for each started 11 seconds of processing time (for example, 12 seconds of processing = 2 units = $0.024).
- The example request below took 2.2 seconds of processing, so it cost $0.012 (1 unit).
- One request returns one image. Larger `width` and `height` or more `steps` take longer, so they can use more units.
- **Failed or cancelled predictions are not billed.**
- **GET requests to check prediction status** are free and don't count toward API unit usage.
- **No monthly subscription fee.**

## API Documentation

### Base URL
All API requests go to: `https://prod.api.market/api/v1/magicapi/realistic-image-generation-lucataco-realistic-vision-v5-1`

### Authentication
Send your api.market API key in the `x-api-market-key` header:
```
x-api-market-key: YOUR_API_MARKET_KEY
```

### Asynchronous Processing
**IMPORTANT**: This API is asynchronous. The flow is:
1. Send a POST request to `/predictions`. A successful request returns **201 Created** with a prediction `id` and a `status` of `starting` or `processing`.
2. Poll GET `/predictions/{id}` with that ID.
3. Keep polling while `status` is `starting` or `processing`.
4. Stop when `status` is `succeeded` (read `output`), `failed` or `canceled` (read `error`).

A polling interval of 1 second and an overall timeout of 600 seconds (10 minutes) work well. The example request took about 2 seconds of processing.

### Endpoints

#### Create a Prediction
```bash
curl -X POST "https://prod.api.market/api/v1/magicapi/realistic-image-generation-lucataco-realistic-vision-v5-1/predictions" \
  -H "Content-Type: application/json" \
  -H "x-api-market-key: YOUR_API_MARKET_KEY" \
  -d '{
    "version": "2c8e954decbf70b7607a4414e5785ef9e4de4b8c51d50fb8b8b349160e0ef6bb",
    "input": {
      "seed": 1339,
      "steps": 20,
      "width": 512,
      "height": 728,
      "prompt": "RAW photo, a portrait photo of a latina woman in casual clothes, natural skin, 8k uhd, high quality, film grain, Fujifilm XT3",
      "guidance": 5,
      "scheduler": "EulerA",
      "negative_prompt": "(deformed iris, deformed pupils, semi-realistic, cgi, 3d, render, sketch, cartoon, drawing, anime:1.4), text, close up, cropped, out of frame, worst quality, low quality, jpeg artifacts, ugly, duplicate, morbid, mutilated, extra fingers, mutated hands, poorly drawn hands, poorly drawn face, mutation, deformed, blurry, dehydrated, bad anatomy, bad proportions, extra limbs, cloned face, disfigured, gross proportions, malformed limbs, missing arms, missing legs, extra arms, extra legs, fused fingers, too many fingers, long neck"
    }
  }'
```

Response (201 Created):
```json
{
  "id": "4ba9psyn0hrmt0d1ccsrg5pay0",
  "version": "2c8e954decbf70b7607a4414e5785ef9e4de4b8c51d50fb8b8b349160e0ef6bb",
  "status": "starting",
  "created_at": "2026-10-22T10:41:43.819Z"
}
```

#### Check Prediction Status
```bash
curl -X GET "https://prod.api.market/api/v1/magicapi/realistic-image-generation-lucataco-realistic-vision-v5-1/predictions/{id}" \
  -H "x-api-market-key: YOUR_API_MARKET_KEY"
```

Response when the prediction has finished (200 OK):
```json
{
  "id": "4ba9psyn0hrmt0d1ccsrg5pay0",
  "status": "succeeded",
  "output": "https://blog.api.market/wp-content/uploads/2026/10/realistic-vision-v5-1-output-4ba9psyn-api-market-1.png",
  "error": null,
  "created_at": "2026-10-22T10:41:43.819Z",
  "started_at": "2026-10-22T10:42:35.511Z",
  "completed_at": "2026-10-22T10:42:37.674Z"
}
```

`output` is a single URL string pointing to the generated image.

### Status Codes
- **201 Created**: prediction created (POST `/predictions`). This is the normal success response.
- **200 OK**: prediction details returned (GET `/predictions/{id}`).
- **400 Bad Request**: invalid input, for example a `width` or `height` above 1920 or a `scheduler` that is not in the list.
- **401 Unauthorized**: missing or invalid API key.
- **404 Not Found**: no prediction with that ID.
- **429 Too Many Requests**: rate limit exceeded.
- **500 Internal Server Error** or **503 Service Unavailable**: temporary server problem; retry later.

## Rate Limits
All plans allow 10 requests per second. Requests above that return `429 Too Many Requests`; back off before retrying and honour any `Retry-After` header. Polling a prediction with GET is free but still counts toward the per-second limit, so poll every 1 to 5 seconds rather than in a tight loop.

## Error Handling
- Check the HTTP status code of every request and read the response body for the error message.
- A prediction can also end with `status` set to `failed`; the `error` field then explains why. Failed predictions are not billed.
- Retry 429, 500 and 503 responses with exponential backoff. Fix the input before retrying a 400.

## Implementation Guide
### Example Code

#### JavaScript
```javascript
const apiKey = "YOUR_API_MARKET_KEY";
const baseUrl = "https://prod.api.market/api/v1/magicapi/realistic-image-generation-lucataco-realistic-vision-v5-1";

async function createAndWaitForPrediction(input) {
  const response = await fetch(`${baseUrl}/predictions`, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "x-api-market-key": apiKey
    },
    body: JSON.stringify({ version: "2c8e954decbf70b7607a4414e5785ef9e4de4b8c51d50fb8b8b349160e0ef6bb", input })
  });

  if (response.status !== 201) {
    throw new Error(`API error: ${response.status} ${await response.text()}`);
  }

  const prediction = await response.json();
  return pollForResults(prediction.id);
}

const delay = (ms) => new Promise((resolve) => setTimeout(resolve, ms));

async function pollForResults(predictionId) {
  const maxTimeout = 600000;
  const pollInterval = 1000;
  const startTime = Date.now();

  while (Date.now() - startTime < maxTimeout) {
    const response = await fetch(`${baseUrl}/predictions/${predictionId}`, {
      headers: { "x-api-market-key": apiKey }
    });

    if (!response.ok) {
      throw new Error(`API error: ${response.status} ${await response.text()}`);
    }

    const prediction = await response.json();

    if (prediction.status === "succeeded") {
      return prediction.output;
    }

    if (prediction.status === "failed" || prediction.status === "canceled") {
      throw new Error(`Prediction ${prediction.status}: ${prediction.error || "Unknown error"}`);
    }

    await delay(pollInterval);
  }

  throw new Error("Prediction timed out after 10 minutes");
}

createAndWaitForPrediction({
    "seed": 1339,
    "steps": 20,
    "width": 512,
    "height": 728,
    "prompt": "RAW photo, a portrait photo of a latina woman in casual clothes, natural skin, 8k uhd, high quality, film grain, Fujifilm XT3",
    "guidance": 5,
    "scheduler": "EulerA",
    "negative_prompt": "(deformed iris, deformed pupils, semi-realistic, cgi, 3d, render, sketch, cartoon, drawing, anime:1.4), text, close up, cropped, out of frame, worst quality, low quality, jpeg artifacts, ugly, duplicate, morbid, mutilated, extra fingers, mutated hands, poorly drawn hands, poorly drawn face, mutation, deformed, blurry, dehydrated, bad anatomy, bad proportions, extra limbs, cloned face, disfigured, gross proportions, malformed limbs, missing arms, missing legs, extra arms, extra legs, fused fingers, too many fingers, long neck"
  }).then((output) => console.log(output));
```

#### Python
```python
import time
import requests

API_KEY = "YOUR_API_MARKET_KEY"
BASE_URL = "https://prod.api.market/api/v1/magicapi/realistic-image-generation-lucataco-realistic-vision-v5-1"


def create_and_wait_for_prediction(input_data):
    headers = {"Content-Type": "application/json", "x-api-market-key": API_KEY}
    response = requests.post(
        f"{BASE_URL}/predictions",
        headers=headers,
        json={"version": "2c8e954decbf70b7607a4414e5785ef9e4de4b8c51d50fb8b8b349160e0ef6bb", "input": input_data},
    )

    if response.status_code != 201:
        raise Exception(f"API error: {response.status_code} {response.text}")

    return poll_for_results(response.json()["id"])


def poll_for_results(prediction_id):
    max_timeout = 600
    poll_interval = 1
    headers = {"x-api-market-key": API_KEY}
    start_time = time.time()

    while time.time() - start_time < max_timeout:
        response = requests.get(f"{BASE_URL}/predictions/{prediction_id}", headers=headers)

        if response.status_code != 200:
            raise Exception(f"API error: {response.status_code} {response.text}")

        prediction = response.json()

        if prediction["status"] == "succeeded":
            return prediction["output"]

        if prediction["status"] in ("failed", "canceled"):
            raise Exception(f"Prediction {prediction['status']}: {prediction.get('error') or 'Unknown error'}")

        time.sleep(poll_interval)

    raise Exception("Prediction timed out after 10 minutes")


print(create_and_wait_for_prediction({
    "seed": 1339,
    "steps": 20,
    "width": 512,
    "height": 728,
    "prompt": "RAW photo, a portrait photo of a latina woman in casual clothes, natural skin, 8k uhd, high quality, film grain, Fujifilm XT3",
    "guidance": 5,
    "scheduler": "EulerA",
    "negative_prompt": "(deformed iris, deformed pupils, semi-realistic, cgi, 3d, render, sketch, cartoon, drawing, anime:1.4), text, close up, cropped, out of frame, worst quality, low quality, jpeg artifacts, ugly, duplicate, morbid, mutilated, extra fingers, mutated hands, poorly drawn hands, poorly drawn face, mutation, deformed, blurry, dehydrated, bad anatomy, bad proportions, extra limbs, cloned face, disfigured, gross proportions, malformed limbs, missing arms, missing legs, extra arms, extra legs, fused fingers, too many fingers, long neck"
}))
```

## FAQ
- **Is `prompt` required?**
  - No. The schema gives it a default portrait prompt, but you will normally send your own.
- **What guidance value should I use?**
  - The schema recommends 3.5 to 7. The default is 5.
- **How large can images be?**
  - `width` and `height` go up to 1920 pixels each. The default is 512 x 728.
- **How do I get the same image twice?**
  - Send the same input with a fixed `seed` other than 0. `seed` 0 (default) picks a random seed.
- **How much does a request cost?**
  - $0.012 per API unit, and one unit covers up to 11 seconds of processing. The example took about 2.2 seconds and cost $0.012.
- **What if my prediction fails?**
  - Failed predictions are not billed. Read the `error` field, adjust the input and try again.

## Contact Us
If you have any questions, reach out to us through the chat on the bottom right of the page. You can also email our support team at hello@magicapi.com.


Generate photorealistic portraits and scenes from text with Realistic Vision v5.1 with VAE, at up to 1920 x 1920 pixels. $0.012 per API unit, pay as you go.