# Veo 3.1 API

> Το κορυφαίο μοντέλο βίντεο της Google, clip 4 έως 8 δευτερολέπτων με διάλογο και ήχο, έως 4K.

Το Veo 3.1 παράγει εξαιρετικά ρεαλιστικό υλικό με συγχρονισμένο συγχρονισμό χειλιών, ήχο περιβάλλοντος και μουσική που δημιουργούνται στην ίδια διέλευση, και ακολουθεί πιστά τις οδηγίες κάμερας και φωτισμού. Τα κλιπ διαρκούν 4, 6 ή 8 δευτερόλεπτα, σε οριζόντιο ή κατακόρυφο προσανατολισμό, στα 720p, 1080p ή 4K. Ο ήχος μπορεί να απενεργοποιηθεί για χαμηλότερη τιμή.

- Model id: `veo3.1`
- Made by: Google
- Category: Text to Video
- Output: video
- Price: from $0.20 / second (8 s ≈ $1.60) (cheapest run $1.60 (1600 API credits))
- Run: `POST https://api.doitong.com/v1/run/veo3.1`
- Quote: `POST https://api.doitong.com/v1/quote/veo3.1`
- Docs page: https://doitong.com/el/developers/models/veo3.1

## Pricing

Price: **from $0.20 / second (8 s ≈ $1.60)** (the lowest tier; the quote prices your exact input). Billed per second of output (`duration`, default 8).

Price rules (the first rule that matches the input wins; a parameter you leave out counts as its default):

- When `resolution` = 4k and `generate_audio` = true: $0.60 (600 API credits) / second
- When `resolution` = 4k: $0.40 (400 API credits) / second
- When `generate_audio` = true: $0.40 (400 API credits) / second

The full example input below costs $3.20 = 3200 API credits (8 s × 400 API credits).

Prices are the upstream price in USD, paid from the API balance in API credits (1000 API credits = 1 USD). `POST https://api.doitong.com/v1/quote/veo3.1` with the same JSON body returns the exact price for that input; the quote is exactly what a run charges. Invalid input is never charged and failed or canceled requests are refunded automatically.

## Input parameters

| Parameter | Canonical name | Type | Required | Default | Allowed values / range | Description |
|---|---|---|---|---|---|---|
| `prompt` |  | string | yes |  | ≤ 20000 characters | Text περιγραφή του επιθυμητού βίντεο προς παραγωγή. |
| `aspect_ratio` |  | enum (string) | no | `16:9` | `16:9`, `9:16` | Αναλογία πλάτους προς ύψος για το παραγόμενο βίντεο. |
| `duration` |  | enum (string) | no | `8s` | `4s`, `6s`, `8s` | Διάρκεια του βίντεο εξόδου. |
| `negative_prompt` |  | string \| null | no |  |  | Αρνητικό prompt που καθοδηγεί την παραγωγή βίντεο. |
| `resolution` |  | enum (string) | no | `720p` | `720p`, `1080p`, `4k` | Ανάλυση που χρησιμοποιείται για το βίντεο εξόδου. |
| `generate_audio` |  | boolean | no | `true` |  | Ελέγχει αν το βίντεο περιλαμβάνει παραγόμενο ήχο. |
| `seed` |  | integer \| null | no |  |  | Τιμή seed που αρχικοποιεί την παραγωγή τυχαίων αριθμών. |
| `auto_fix` |  | boolean | no | `true` |  | Αυτόματη επανεγγραφή prompt για προσπάθεια επίλυσης αποτυχιών στους ελέγχους πολιτικής περιεχομένου ή σε άλλη επικύρωση. |
| `safety_tolerance` |  | enum (string) | no | `4` | `1`, `2`, `3`, `4`, `5`, `6` | Ορίστε την ανοχή εποπτείας περιεχομένου μεταξύ του λιγότερο περιοριστικού επιπέδου, 6, και του αυστηρότερου, 1, που αποκλείει το περισσότερο περιεχόμενο. |

## Example input

Required parameters only:

```json
{
  "prompt": "A street interviewer in New York asks a passer-by \"Did you hear the news?\" and she laughs \"Everyone has!\""
}
```

A fuller example:

```json
{
  "prompt": "A street interviewer in New York asks a passer-by \"Did you hear the news?\" and she laughs \"Everyone has!\"",
  "duration": 8,
  "resolution": "720p"
}
```

## Run it

Set `DOITONG_API_KEY` to a key from https://doitong.com/developers/dashboard#keys. `?wait=20` returns the finished request in the same call when it is ready within 20 seconds; otherwise poll `GET /requests/{id}` (it also accepts `?wait=`), or pass `webhook_url`.

### curl

```bash
# Run the model; wait up to 20 s for the finished result in the same call
curl -X POST "https://api.doitong.com/v1/run/veo3.1?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "A street interviewer in New York asks a passer-by \"Did you hear the news?\" and she laughs \"Everyone has!\"",
    "duration": 8,
    "resolution": "720p"
  }'

# Still "queued" or "running"? Poll with the id from the response:
curl "https://api.doitong.com/v1/requests/REQUEST_ID?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY"
```

### JavaScript

```javascript
const API = "https://api.doitong.com/v1";
const headers = {
  "Authorization": "Bearer " + process.env.DOITONG_API_KEY,
  "Content-Type": "application/json",
};

// Run the model; wait up to 20 s for the finished result in the same call
let res = await fetch(API + "/run/veo3.1?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "prompt": "A street interviewer in New York asks a passer-by \"Did you hear the news?\" and she laughs \"Everyone has!\"",
    "duration": 8,
    "resolution": "720p"
  }),
});
let request = await res.json();
if (!res.ok) throw new Error(request.error.code + ": " + request.error.message);

// Not finished yet: long-poll until it is
while (request.status === "queued" || request.status === "running") {
  res = await fetch(API + "/requests/" + request.id + "?wait=20", { headers });
  request = await res.json();
}
if (request.status !== "succeeded") throw new Error(JSON.stringify(request.error));
console.log(request.outputs.map((o) => o.url), request.cost.credits + " API credits ($" + request.cost.usd + ")");
```

### Python

```python
import os
import requests

API = "https://api.doitong.com/v1"
headers = {"Authorization": "Bearer " + os.environ["DOITONG_API_KEY"]}

payload = {
    "prompt": "A street interviewer in New York asks a passer-by \"Did you hear the news?\" and she laughs \"Everyone has!\"",
    "duration": 8,
    "resolution": "720p",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/veo3.1", params={"wait": 20}, json=payload, headers=headers)
request = r.json()
if not r.ok:
    raise RuntimeError(request["error"]["code"] + ": " + request["error"]["message"])

# Not finished yet: long-poll until it is
while request["status"] in ("queued", "running"):
    request = requests.get(API + "/requests/" + request["id"], params={"wait": 20}, headers=headers).json()
if request["status"] != "succeeded":
    raise RuntimeError(request["error"])
print([o["url"] for o in request["outputs"]], request["cost"]["credits"], "API credits", "$" + request["cost"]["usd"])
```

### MCP

The MCP server at `https://api.doitong.com/v1/mcp` exposes the tools `search_models`, `get_model`, `quote`, `run`, `get_request`, `cancel_request`, `list_requests`, `create_upload` and `get_account`. A `run` call for this model:

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "run",
    "arguments": {
      "model_id": "veo3.1",
      "input": {
        "prompt": "A street interviewer in New York asks a passer-by \"Did you hear the news?\" and she laughs \"Everyone has!\"",
        "duration": 8,
        "resolution": "720p"
      },
      "wait_seconds": 20
    }
  }
}
```

## Response

Every call returns a request object. `status` is one of `queued`, `running`, `succeeded`, `failed`, `canceled`. `outputs` lists the generated files with URLs on our storage (kept forever, or 7 days with `?storage=temporary`; `storage` says which); `output` is the model's own result object with the same URLs.

```json
{
  "id": "req_8k2m4q7x1z9c3v5b6n0p2r4t",
  "object": "request",
  "model": "veo3.1",
  "status": "succeeded",
  "created_at": "2026-10-20T12:00:00Z",
  "started_at": "2026-10-20T12:00:02Z",
  "completed_at": "2026-10-20T12:00:09Z",
  "queue_position": null,
  "cost": {
    "credits": 3200,
    "usd": "3.20",
    "charged": 3200,
    "refunded": 0
  },
  "input": {
    "prompt": "A street interviewer in New York asks a passer-by \"Did you hear the news?\" and she laughs \"Everyone has!\"",
    "duration": 8,
    "resolution": "720p"
  },
  "output": {
    "video": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_name": "0-output.mp4",
      "file_size": 1843200
    }
  },
  "outputs": [
    {
      "type": "video",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp4",
      "content_type": "video/mp4",
      "file_size": 1843200,
      "width": 1280,
      "height": 720,
      "duration": 5,
      "stored": true
    }
  ],
  "error": null,
  "metrics": {
    "inference_seconds": 6.8
  },
  "urls": {
    "self": "https://api.doitong.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t",
    "cancel": "https://api.doitong.com/v1/requests/req_8k2m4q7x1z9c3v5b6n0p2r4t/cancel"
  }
}
```

### Output fields (`output`)

| Field | Type | Description |
|---|---|---|
| `video` | object {url, content_type, file_name, file_size} | Βίντεο που παράγεται από το μοντέλο. |

## Related models

- [Veo 3.1 Fast](https://doitong.com/developers/models/veo3.1/fast.md) (`veo3.1/fast`): from $0.10 / second
- [Veo 3.1 Fast Image to Video](https://doitong.com/developers/models/veo3.1/fast/image-to-video.md) (`veo3.1/fast/image-to-video`): from $0.10 / second
- [Veo 3.1 Image to Video](https://doitong.com/developers/models/veo3.1/image-to-video.md) (`veo3.1/image-to-video`): from $0.20 / second
- [Veo3.1 Fast First Last Frame to Video](https://doitong.com/developers/models/veo3.1/fast/first-last-frame-to-video.md) (`veo3.1/fast/first-last-frame-to-video`): from $0.10 / second
- [Veo3.1 First Last Frame to Video](https://doitong.com/developers/models/veo3.1/first-last-frame-to-video.md) (`veo3.1/first-last-frame-to-video`): from $0.20 / second
- [Veo3.1 Reference to Video](https://doitong.com/developers/models/veo3.1/reference-to-video.md) (`veo3.1/reference-to-video`): from $0.20 / second
- [FLUX 3 Max Text to Video](https://doitong.com/developers/models/blackforestlabs/flux-3-max/text-to-video.md) (`blackforestlabs/flux-3-max/text-to-video`): from $0.0425 / second of output video
- [Grok Imagine Video 1.5 Text to Video](https://doitong.com/developers/models/xai/grok-imagine-video/v1.5/text-to-video.md) (`xai/grok-imagine-video/v1.5/text-to-video`): from $0.08 / second

## Links

- HTML page: https://doitong.com/developers/models/veo3.1
- All models and guides for AI agents: https://doitong.com/developers/llms.txt
- OpenAPI 3.1 with this model's typed request body: https://doitong.com/developers/openapi.json?model=veo3.1
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/veo3.1