> 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. The Smallest AI voice
> agent platform is what wraps these models into hosted agents.

# Quickstart

> Transcribe your first audio file in under 60 seconds with Pulse Pro.

## Step 1: Get Your API Key

Open the [API Keys page](https://app.smallest.ai/dashboard/api-keys?utm_source=documentation\&utm_medium=speech-to-text-quickstart) in the [Smallest AI console](https://app.smallest.ai/dashboard).

![Smallest AI dashboard with API Keys highlighted under Developer section in the left sidebar](/_fern-img/2485b6d1a1e2784842aed6627f0ff407382aeff10d4970982f2024e43680c372.webp)

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

![API Keys page showing the Create API Key button](/_fern-img/9bee0666597b5f1da251ddc4d521f47d0275f4fb74dc5be1b89a0ca78b8bad3d.webp)![Create New API Key dialog with API Name field and Create API Key button](/_fern-img/91874b47799b60d6ff225693ef6de002e3bdd25fc056d69a5ec6fb62a7872fde.webp)

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

![API Keys dashboard showing the newly created key with copy icon highlighted](/_fern-img/0c9cbc1ceced23a9e01808372ed3438e0a6fd6286f87128b69240dfefadf5e74.webp)

Export the key in your terminal:

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

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

## Step 2: Transcribe Audio

Here's the sample audio we'll transcribe:

Paste this cURL (no install required). It downloads the sample and pipes it into Pulse Pro as raw bytes:

```bash
curl -sL "https://github.com/smallest-inc/cookbook/raw/main/speech-to-text/getting-started/samples/audio.wav" | \
  curl -X POST "https://api.smallest.ai/waves/v1/stt/?model=pulse-pro&language=en" \
    -H "Authorization: Bearer $SMALLEST_API_KEY" \
    -H "Content-Type: application/octet-stream" \
    --data-binary @-
```

You'll get back:

```json
{
  "status": "success",
  "transcription": "This is a sample audio file for testing speech-to-text transcription with the Pulse API.",
  "language": "en",
  "metadata": { "duration": 5.6, "processing_time_ms": 109.58, "rtfx": 51.1, "num_chunks": 1 },
  "request_id": "354c932b-3c3a-473c-a6e7-fd497ba10d96"
}
```

> **Note**
>
> This quickstart uses **Pulse Pro**, our leaderboard-ranked English model. If you need multilingual transcription (21 streaming + 12 pre-recorded languages) or streaming, swap `?model=pulse-pro` for `?model=pulse`. See the [Pulse model card](/model-cards/speech-to-text/pulse) for the full language list.

## Step 3: Build It Into Your App

The snippets below use **Pulse Pro** (`?model=pulse-pro`). For multilingual audio, swap to `?model=pulse` and set the appropriate `language` code. Both models share the same `/waves/v1/stt/` endpoint and request shape.

**`cURL`**

```bash cURL
curl -sL "https://github.com/smallest-inc/cookbook/raw/main/speech-to-text/getting-started/samples/audio.wav" | \
  curl -X POST "https://api.smallest.ai/waves/v1/stt/?model=pulse-pro&language=en" \
    -H "Authorization: Bearer $SMALLEST_API_KEY" \
    -H "Content-Type: application/octet-stream" \
    --data-binary @-
```

**`Python`**

```python Python
import os
import requests

API_KEY = os.environ["SMALLEST_API_KEY"]
SAMPLE_URL = "https://github.com/smallest-inc/cookbook/raw/main/speech-to-text/getting-started/samples/audio.wav"

audio = requests.get(SAMPLE_URL).content

response = requests.post(
    "https://api.smallest.ai/waves/v1/stt/",
    params={"model": "pulse-pro", "language": "en"},
    headers={
        "Authorization": f"Bearer {API_KEY}",
        "Content-Type": "application/octet-stream",
    },
    data=audio,
    timeout=120,
)

response.raise_for_status()
print(response.json()["transcription"])
```

**`JavaScript`**

```javascript JavaScript
const audioResponse = await fetch("https://github.com/smallest-inc/cookbook/raw/main/speech-to-text/getting-started/samples/audio.wav");
const audio = Buffer.from(await audioResponse.arrayBuffer());

const params = new URLSearchParams({ model: "pulse-pro", language: "en" });
const response = await fetch(`https://api.smallest.ai/waves/v1/stt/?${params}`, {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.SMALLEST_API_KEY}`,
    "Content-Type": "application/octet-stream",
  },
  body: audio,
});

if (!response.ok) throw new Error(await response.text());
console.log((await response.json()).transcription);
```

> **Note**
>
> For Pulse Pro, `language` must be `en`. For Pulse, set `language` to the known code (`en`, `hi`, `es`, etc.) for best accuracy, or use a regional aggregator for unknown audio. Aggregators differ by mode: pre-recorded supports `multi-eu` and `multi-asian`; streaming supports `north_indic`, `multi-asian` (US region only, contact sales for India), and `multi-south-indic` (India region only, Beta). See the [Pulse model card](/model-cards/speech-to-text/pulse) for the full per-mode language matrix.

> **Note**
>
> For browser or mobile clients, keep the API key on your server and mint a [short-lived access token](/api-reference/token-based-authentication) for the client.

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

## Step 4: Explore Features

#### [Real-Time Transcription](/models/speech-to-text/realtime-web-socket/quickstart)

Stream audio via WebSocket for live transcription.

#### [Speaker Diarization](/models/speech-to-text/features/diarization)

Identify and label different speakers.

#### [Word Timestamps](/models/speech-to-text/features/word-timestamps)

Precise timing for each transcribed word.

#### [Emotion Detection](/models/speech-to-text/features/emotion-detection)

Analyze emotional tone in speech.

#### [Model card](/model-cards/speech-to-text/pulse)

Benchmarks, capabilities, pricing.

Full endpoint spec: [Pulse API Reference](/api-reference/models)

## Need Help?

#### [Join Discord](https://discord.gg/9WtSXv26WE)

Ask questions and get help from the community.

Or email [support@smallest.ai](mailto:support@smallest.ai).

> Transcribe your first audio file in under 60 seconds with Pulse Pro.