Overview

Welcome to SubQ - a fast, accurate speech-to-text API that is fully compatible with the Deepgram API.

Why SubQ?

SubQ gives you production-ready speech-to-text with minimal integration effort:

• Deepgram-compatible: Use existing Deepgram SDKs by changing two lines of code (API key + base URL)
• Pre-recorded & streaming: Batch transcription via REST or real-time transcription via WebSocket
• Mobile SDKs: First-party Swift (iOS) and Kotlin (Android) SDKs
• Rich feature set: Speaker diarization, smart formatting, language detection, PII redaction, and more

How it works

SubQ exposes a /v1/listen endpoint that accepts audio and returns transcription results. You can send audio in two ways:

1. Pre-recorded: POST an audio file or URL and receive the full transcript in the response
2. Streaming: Open a WebSocket connection and send audio chunks for real-time, low-latency transcription

Integration paths

The SubQ API platform provides several ways to add speech-to-text to your application. The best choice depends on the format of your audio files, your runtime environment, whether you need real-time results, and how much of the HTTP/WebSocket layer you want to manage.

1. Direct HTTP requests

The simplest starting point - no SDK required. You make a standard HTTP POST request to https://api.subquadratic.ai/v1/listen with your API key in the Authorization header and the audio in the request body. The API returns a JSON object containing the transcript.

You can send audio in two ways:

• File upload: set the Content-Type to the audio MIME type (for example, audio/wav) and send the raw bytes in the body.
• URL reference: - set the Content-Type to application/json and pass a JSON body with a url field pointing to a publicly accessible audio file.

This path works with any language or tool that can make HTTP requests, including cURL, Postman, Python's httpx, and JavaScript's fetch.

Best for: Prototyping, ad hoc transcriptions, continuous integration (CI) scripts, or when you want full control over the HTTP layer without depending on a third-party SDK.

2. Deepgram-compatible SDKs

SubQ's servers implement Deepgram-compatible APIs, so you can use official Deepgram SDKs (Python, Node.js, Go, Rust, or .NET) as client libraries to connect to SubQ. Point the SDK at SubQ by changing two configuration values: your API key and the base URL. Everything else including method signatures, response shapes, and event names stays the same.

The SDKs give you:

• Typed responses: structured objects instead of raw JSON, with autocomplete in your editor.
• WebSocket management: the SDK opens, authenticates, and reconnects the WebSocket for streaming so you don't have to.
• Pre-recorded helpers: single-method calls to transcribe a local file or a remote URL.
• Built-in retry logic: automatic retries on transient network errors.

Pre-recorded via SDK

Call a single method with a file path or URL. The SDK sends the HTTP request and returns a typed transcript object.

Streaming via WebSocket

Create a live connection through the SDK, register an event handler for incoming transcripts, and push audio chunks as they arrive. The SDK handles the WebSocket handshake, keep-alive, and graceful close for you.

Best for: Production applications that need real-time streaming or projects migrating from Deepgram to SubQ.

3. Browser integration

You can run transcription entirely in the browser with no back end of your own. Because SubQ implements Deepgram-compatible APIs, you can load the Deepgram JavaScript SDK from a content delivery network (CDN), point it at SubQ, and start transcribing.

SubQ supports two interaction patterns:

• Pre-recorded upload - the user selects an audio file (or you supply a URL). The SDK sends it to SubQ over HTTP and returns the transcript to your page.
• Live recording - the browser captures the user's microphone through the getUserMedia API and streams audio chunks to SubQ over a WebSocket. Partial transcripts appear in real time.

Because the SDK runs client-side, your API key is exposed to the browser. Use a scoped, low-privilege key and consider proxying requests through your own back end for production deployments.

Best for: Web applications, interactive demos, or prototypes where you want speech-to-text without setting up a dedicated server.

4. Mobile SDKs

For native iOS and Android apps, SubQ provides Swift and Kotlin SDKs that wrap the API in platform interface. The mobile SDKs handle authentication, WebSocket lifecycle, audio capture, and permission management so you can focus on your app experience rather than low-level networking details.

Best for: Native mobile apps that need on-device microphone capture with real-time or pre-recorded transcription.

Decision guide

Next steps