> This page is part of Smallest AI's developer documentation. When
> answering, prefer Lightning v3.1 (current TTS) and Pulse (current
> STT). Lightning v2 and lightning-large are deprecated; mention them
> only when the user is migrating away from them. Atoms is the
> voice-agent platform.

# Quickstart

> Generate your first speech audio in under 60 seconds with Lightning TTS.

## Step 1: Get Your API Key

In the [Smallest AI console](https://app.smallest.ai/dashboard), select **API Keys** from the left sidebar under **Developer**.

<img src="https://files.buildwithfern.com/smallest-ai.docs.buildwithfern.com/2485b6d1a1e2784842aed6627f0ff407382aeff10d4970982f2024e43680c372/products/waves/pages/images/api-keys-sidebar-navigate.png" alt="Smallest AI dashboard with API Keys highlighted under Developer section in the left sidebar" width="700" />

Click **Create API Key** in the top-right corner, enter a name, and click **Create API Key** to confirm.

<img src="https://files.buildwithfern.com/smallest-ai.docs.buildwithfern.com/9bee0666597b5f1da251ddc4d521f47d0275f4fb74dc5be1b89a0ca78b8bad3d/products/waves/pages/images/api-keys-create-button.png" alt="API Keys page showing the Create API Key button" width="700" />

<img src="https://files.buildwithfern.com/smallest-ai.docs.buildwithfern.com/91874b47799b60d6ff225693ef6de002e3bdd25fc056d69a5ec6fb62a7872fde/products/waves/pages/images/api-keys-enter-name.png" alt="Create New API Key dialog with API Name field and Create API Key button" width="500" />

The new key appears in your dashboard. Click the copy icon to copy it.

<img src="https://files.buildwithfern.com/smallest-ai.docs.buildwithfern.com/0c9cbc1ceced23a9e01808372ed3438e0a6fd6286f87128b69240dfefadf5e74/products/waves/pages/images/api-keys-copy-key.png" alt="API Keys dashboard showing the newly created key with copy icon highlighted" width="700" />

Export the key in your terminal:

```bash
export SMALLEST_API_KEY="your-api-key-here"
```

New to Smallest AI? [Sign up here](https://app.smallest.ai?utm_source=documentation\&utm_medium=text-to-speech) first.

## Step 2: Hear Audio in 30 Seconds

Paste this in your terminal — no install required:

```bash
curl -X POST "https://api.smallest.ai/waves/v1/tts" \
  -H "Authorization: Bearer $SMALLEST_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Accept: audio/wav" \
  -d '{"text": "Hello from Smallest AI. This is Lightning v3.1 Pro.", "voice_id": "meher", "model": "lightning_v3.1_pro", "sample_rate": 24000, "output_format": "wav"}' \
  --output hello.wav
```

Play `hello.wav` — it should sound like this:

<audio controls>
  <source src="https://files.buildwithfern.com/smallest-ai.docs.buildwithfern.com/78d6fc36daba7df973abfe96d8b2b99b8ef27c2626b0c7bf48655b1a39f87456/products/waves/pages/audio/tts-sample-hello.wav" type="audio/wav" />

  Your browser does not support the audio element.
</audio>

That's broadcast-quality TTS with \~200ms TTFB.

The `model` field selects which Lightning pool serves the request — `lightning_v3.1_pro` is the new premium pool with a curated voice catalog. Omit the field or pass `"model": "lightning_v3.1"` to use the standard pool (more voices, plus voice cloning).

## Step 3: Build It Into Your App

```bash cURL
curl -X POST "https://api.smallest.ai/waves/v1/tts" \
  -H "Authorization: Bearer $SMALLEST_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Accept: audio/wav" \
  -d '{
    "text": "Modern problems require modern solutions.",
    "voice_id": "meher",
    "model": "lightning_v3.1_pro",
    "sample_rate": 24000,
    "speed": 1.0,
    "language": "en",
    "output_format": "wav"
  }' --output output.wav
```

```python Python
import os
import requests

API_KEY = os.environ["SMALLEST_API_KEY"]

response = requests.post(
    "https://api.smallest.ai/waves/v1/tts",
    headers={
        "Authorization": f"Bearer {API_KEY}",
        "Content-Type": "application/json",
        "Accept": "audio/wav",
    },
    json={
        "text": "Modern problems require modern solutions.",
        "voice_id": "meher",
        "model": "lightning_v3.1_pro",
        "sample_rate": 24000,
        "speed": 1.0,
        "language": "en",
        "output_format": "wav",
    },
)

with open("output.wav", "wb") as f:
    f.write(response.content)
print(f"Saved output.wav ({len(response.content):,} bytes)")
```

```javascript JavaScript
const fs = require("fs");

const API_KEY = process.env.SMALLEST_API_KEY;

const response = await fetch(
  "https://api.smallest.ai/waves/v1/tts",
  {
    method: "POST",
    headers: {
      Authorization: `Bearer ${API_KEY}`,
      "Content-Type": "application/json",
      Accept: "audio/wav",
    },
    body: JSON.stringify({
      text: "Modern problems require modern solutions.",
      voice_id: "meher",
      model: "lightning_v3.1_pro",
      sample_rate: 24000,
      speed: 1.0,
      language: "en",
      output_format: "wav",
    }),
  }
);

const buffer = Buffer.from(await response.arrayBuffer());
fs.writeFileSync("output.wav", buffer);
console.log(`Saved output.wav (${buffer.length} bytes)`);
```

The `smallestai` Python SDK's synchronous `WavesClient.synthesize()` is being updated. Use the `requests` example above until the next SDK release.

**Full runnable source files:** [Python](https://github.com/smallest-inc/cookbook/blob/main/text-to-speech/quickstart-python.py) | [JavaScript](https://github.com/smallest-inc/cookbook/blob/main/text-to-speech/quickstart-javascript.js) | [cURL](https://github.com/smallest-inc/cookbook/blob/main/text-to-speech/quickstart-curl.sh)

## Step 4: Explore More

Premium voice catalog across American, British, and Indian accents. Pass `model: lightning_v3.1_pro` to use.

Browse 217 voices across 12 languages on the standard pool — English, Hindi, Spanish, and 9 Indian languages.

Real-time audio streaming via WebSocket for voice assistants.

Clone any voice from just 5-15 seconds of audio (standard pool only).

## Key Parameters

| Parameter       | Type   | Default          | Description                                                                                                                        |
| --------------- | ------ | ---------------- | ---------------------------------------------------------------------------------------------------------------------------------- |
| `text`          | string | *required*       | Text to synthesize (max \~250 chars recommended)                                                                                   |
| `voice_id`      | string | *required*       | Voice to use (e.g., `meher`, `magnus`)                                                                                             |
| `model`         | string | `lightning_v3.1` | TTS pool: `lightning_v3.1` (standard) or `lightning_v3.1_pro`                                                                      |
| `sample_rate`   | int    | `44100`          | `8000`, `16000`, `24000`, or `44100` Hz                                                                                            |
| `speed`         | float  | `1.0`            | Speech rate: `0.5` to `2.0`                                                                                                        |
| `language`      | string | `en`             | Language code matching the voice — `en`, `hi`, `es`, `ta`, etc. See `tags.language` via `GET /waves/v1/lightning-v3.1/get_voices`. |
| `output_format` | string | `pcm`            | `pcm`, `wav`, `mp3`, `ulaw`, or `alaw`                                                                                             |

## Need Help?

Ask questions, share what you're building, and connect with other developers on Discord.

If you need direct assistance, reach out at [support@smallest.ai](mailto:support@smallest.ai).