# Gemini 3.1 Flash Tts API

> Text-to-speech Gemini 3.1 Flash dengan kawalan gaya sebaris, 30 suara dan sehingga 10 penutur

Menukar `prompt` sehingga 50000 aksara kepada pertuturan. Penyampaian boleh dikawal secara sebaris atau melalui `style_instructions`. Pilih salah satu daripada 30 suara, tetapkan `language_code`, atau gunakan `speakers` (2 hingga 10) untuk audio berbilang penutur. Output ialah mp3, wav atau ogg_opus, dengan `temperature` daripada 0 hingga 2.

- Model id: `gemini-3.1-flash-tts`
- Made by: Google
- Category: Text to Speech
- Output: audio
- Price: $0.05 / 1000 characters (cheapest run $0.05 (50 API credits))
- Run: `POST https://api.doitong.com/v1/run/gemini-3.1-flash-tts`
- Quote: `POST https://api.doitong.com/v1/quote/gemini-3.1-flash-tts`
- Docs page: https://doitong.com/ms/developers/models/gemini-3.1-flash-tts

## Pricing

Price: **$0.05 / 1000 characters**. Billed per character of `prompt` (the price is per 1000 characters).

The full example input below costs $0.003 = 3 API credits (50 characters × 50 API credits / 1000 characters).

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/gemini-3.1-flash-tts` 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 |  | 1 – 50000 characters | Teks sintesis pertuturan untuk Gemini 3.1 Flash TTS; baris berbilang penutur mesti bermula dengan alias daripada medan speakers, seperti dalam 'Alice: Hello!\nBob: Hi!'. Penyampaian boleh dikawal dengan teliti menggunakan tag audio ekspresif seperti [sigh], [laughing], [whispering], dan [short pause], atau arahan bahasa semula jadi sebaris untuk loghat, emosi, rentak dan gaya, seperti 'Say cheerfully: Have a wonderful day!'. |
| `style_instructions` |  | string \| null | no |  | ≤ 4000 characters | Arahan bahasa semula jadi pilihan yang dikekalkan berasingan daripada kandungan yang dituturkan dan disisipkan sebelum prompt untuk membentuk ekspresiviti, loghat, rentak, nada dan emosi. Contohnya termasuk 'Speak warmly and slowly', 'Read this as a dramatic newscast', 'Use a British accent with a cheerful tone', dan 'Whisper mysteriously'. |
| `voice` |  | enum (string) | no | `Kore` | `Achernar`, `Achird`, `Algenib`, `Algieba`, `Alnilam`, `Aoede`, `Autonoe`, `Callirrhoe`, `Charon`, `Despina`, `Enceladus`, `Erinome`, `Fenrir`, `Gacrux`, `Iapetus`, `Kore`, `Laomedeia`, `Leda`, `Orus`, `Pulcherrima`, `Puck`, `Rasalgethi`, `Sadachbia`, `Sadaltager`, `Schedar`, `Sulafat`, `Umbriel`, `Vindemiatrix`, `Zephyr`, `Zubenelgenubi` | Pilihan suara seorang penutur daripada 30 pratetap berbeza; menetapkan speakers menjadikan pilihan ini tidak aktif. Pilihan wanita popular ialah Kore, dengan penyampaian kuat dan tegas, Zephyr, dengan penyampaian terang dan jelas, dan Aoede, dengan penyampaian hangat dan merdu; pilihan lelaki popular ialah Puck, ceria dan bertenaga, serta Charon, tenang dan profesional. |
| `language_code` |  | enum (string) \| null | no |  | `Arabic (Egypt)`, `Bangla (Bangladesh)`, `Dutch (Netherlands)`, `English (India)`, `English (US)`, `French (France)`, `German (Germany)`, `Hindi (India)`, `Indonesian (Indonesia)`, `Italian (Italy)`, `Japanese (Japan)`, `Korean (South Korea)`, `Marathi (India)`, `Polish (Poland)`, `Portuguese (Brazil)`, `Romanian (Romania)`, `Russian (Russia)`, `Spanish (Spain)`, `Tamil (India)`, `Telugu (India)`, `Thai (Thailand)`, `Turkish (Turkey)`, `Ukrainian (Ukraine)`, `Vietnamese (Vietnam)`, `Afrikaans (South Africa)`, `Albanian (Albania)`, `Amharic (Ethiopia)`, `Arabic (World)`, `Armenian (Armenia)`, `Azerbaijani (Azerbaijan)`, `Basque (Spain)`, `Belarusian (Belarus)`, `Bulgarian (Bulgaria)`, `Burmese (Myanmar)`, `Catalan (Spain)`, `Cebuano (Philippines)`, `Chinese Mandarin (China)`, `Chinese Mandarin (Taiwan)`, `Croatian (Croatia)`, `Czech (Czech Republic)`, `Danish (Denmark)`, `English (Australia)`, `English (UK)`, `Estonian (Estonia)`, `Filipino (Philippines)`, `Finnish (Finland)`, `French (Canada)`, `Galician (Spain)`, `Georgian (Georgia)`, `Greek (Greece)`, `Gujarati (India)`, `Haitian Creole (Haiti)`, `Hebrew (Israel)`, `Hungarian (Hungary)`, `Icelandic (Iceland)`, `Javanese (Java)`, `Kannada (India)`, `Konkani (India)`, `Lao (Laos)`, `Latin (Vatican City)`, `Latvian (Latvia)`, `Lithuanian (Lithuania)`, `Luxembourgish (Luxembourg)`, `Macedonian (North Macedonia)`, `Maithili (India)`, `Malagasy (Madagascar)`, `Malay (Malaysia)`, `Malayalam (India)`, `Mongolian (Mongolia)`, `Nepali (Nepal)`, `Norwegian Bokmal (Norway)`, `Norwegian Nynorsk (Norway)`, `Odia (India)`, `Pashto (Afghanistan)`, `Persian (Iran)`, `Portuguese (Portugal)`, `Punjabi (India)`, `Serbian (Serbia)`, `Sindhi (India)`, `Sinhala (Sri Lanka)`, `Slovak (Slovakia)`, `Slovenian (Slovenia)`, `Spanish (Latin America)`, `Spanish (Mexico)`, `Swahili (Kenya)`, `Swedish (Sweden)`, `Urdu (Pakistan)` | Penggantian bahasa sintesis berbilang bahasa: pengesanan automatik daripada teks digunakan melainkan anda menentukan bahasa untuk mengarahkan pertuturan model. |
| `speakers` |  | array of object {voice, speaker_id} \| array of any \| null | no |  |  | Konfigurasi suara yang membolehkan beberapa penutur membaca bahagian teks yang berasingan. Tetapkan setiap penutur kepada suara serta alias speaker_id yang sepadan dengan awalan prompt masing-masing. |
| `temperature` |  | number | no | `1` | 0 – 2 | Tetapan rawak pertuturan, dengan kesan daripada penyampaian fokus dan boleh dijangka pada tetapan rendah hingga penyampaian kreatif dan pelbagai pada tetapan tinggi. |
| `output_format` |  | enum (string) | no | `mp3` | `wav`, `mp3`, `ogg_opus` | Format untuk audio output: mp3 menyediakan fail termampat dan padat serta disyorkan; wav mengandungi PCM tidak termampat dalam bekas WAV pada 24 kHz dengan audio mono 16-bit; ogg_opus menggunakan Opus dalam Ogg untuk keseimbangan kualiti dan saiz yang baik. |

## Example input

Required parameters only:

```json
{
  "prompt": "Hello from Doitong. This is a short test sentence."
}
```

A fuller example:

```json
{
  "prompt": "Hello from Doitong. This is a short test sentence."
}
```

## 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/gemini-3.1-flash-tts?wait=20" \
  -H "Authorization: Bearer $DOITONG_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "Hello from Doitong. This is a short test sentence."
  }'

# 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/gemini-3.1-flash-tts?wait=20", {
  method: "POST",
  headers,
  body: JSON.stringify({
    "prompt": "Hello from Doitong. This is a short test sentence."
  }),
});
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": "Hello from Doitong. This is a short test sentence.",
}

# Run the model; wait up to 20 s for the finished result in the same call
r = requests.post(API + "/run/gemini-3.1-flash-tts", 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": "gemini-3.1-flash-tts",
      "input": {
        "prompt": "Hello from Doitong. This is a short test sentence."
      },
      "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": "gemini-3.1-flash-tts",
  "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": 3,
    "usd": "0.003",
    "charged": 3,
    "refunded": 0
  },
  "input": {
    "prompt": "Hello from Doitong. This is a short test sentence."
  },
  "output": {
    "audio": {
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp3",
      "content_type": "audio/mpeg",
      "file_name": "0-output.mp3",
      "file_size": 1843200
    }
  },
  "outputs": [
    {
      "type": "audio",
      "url": "https://content.doitong.com/dev-api/2026/10/20/req_8k2m4q7x1z9c3v5b6n0p2r4t/0-output.mp3",
      "content_type": "audio/mpeg",
      "file_size": 1843200,
      "duration": 12,
      "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 |
|---|---|---|
| `audio` | object {url, content_type, file_name, file_size} | Fail audio yang dihasilkan oleh penjanaan. |

## Related models

- [Eleven v4 Text to Speech](https://doitong.com/developers/models/elevenlabs/tts/eleven-v4.md) (`elevenlabs/tts/eleven-v4`): $0.08 / 1000 characters
- [MiniMax Speech 2.8 HD](https://doitong.com/developers/models/minimax/speech-2.8-hd.md) (`minimax/speech-2.8-hd`): $0.10 / 1000 characters
- [Gemini 3.8 Flash Lite TTS](https://doitong.com/developers/models/google/gemini-3.8-flash-lite-tts.md) (`google/gemini-3.8-flash-lite-tts`): $0.111 / run
- [Gemini 3.8 Flash TTS](https://doitong.com/developers/models/google/gemini-3.8-flash-tts.md) (`google/gemini-3.8-flash-tts`): $0.045 / run
- [Gemini TTS](https://doitong.com/developers/models/gemini-tts.md) (`gemini-tts`): $0.03 / run
- [Async Text to Speech Pro V1.0](https://doitong.com/developers/models/async/tts-pro/v1.0.md) (`async/tts-pro/v1.0`): $0.01 / 1000 characters
- [Bytedance Seed Speech Text to Speech](https://doitong.com/developers/models/bytedance/seed-speech/tts/v2.md) (`bytedance/seed-speech/tts/v2`): $0.03 / 1000 characters
- [Chatterbox · Speech to Speech](https://doitong.com/developers/models/chatterbox/speech-to-speech.md) (`chatterbox/speech-to-speech`): $0.015 / minute of input audio

## Links

- HTML page: https://doitong.com/developers/models/gemini-3.1-flash-tts
- 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=gemini-3.1-flash-tts
- Errors: https://doitong.com/developers/docs/errors
- Model details as JSON: https://api.doitong.com/v1/models/gemini-3.1-flash-tts