Overview
The FineVoice API gives you programmatic access to a full suite of AI audio capabilities — from text-to-speech and voice conversion to music generation and audio enhancement. All endpoints are served over HTTPS and return JSON responses.
Base URL
https://apis.finevoice.ai
Authentication
Every request must include a valid API key as a Bearer token in the Authorization header.
Authorization: Bearer YOUR_API_KEY
Keep your API key private. Do not expose it in client-side code or public repositories.
API Categories
| Category | Description |
|---|
| Text to Speech | Convert text into natural-sounding speech with emotion tag support |
| Voice Conversion | Transform the voice in an audio file to a different AI voice |
| Speech to Text | Transcribe audio or video with speaker diarization and timestamps |
| Sound Effect Generation | Generate royalty-free sound effects from a prompt or video |
| Audio Separation | Separate vocals, instruments, and stems from audio |
| Podcast Generation | Generate multi-speaker AI podcasts from a prompt or script |
| Task Status | Poll the result of any asynchronous task |
| AI Voices | Browse and search available voice models |
| Voice Design | Design a new AI voice from a text description |
| AI Voice Cloning | Train a custom voice model from a reference audio |
| Music Generation | Generate full songs with vocals and instrumentation |
| Background Music | Generate background music tracks from a prompt |
| Music Cover | Replace vocals in a song with an AI voice |
| Audio Enhancement | Denoise, normalize, remove silences, and more |
Synchronous vs Asynchronous
Some endpoints support an optional useAsync field. When set to true, the API queues the job and immediately returns a taskId. Poll the task status endpoint until the result is ready.
Polling task status
A completed task returns a url (or urls for multi-output tasks) containing the download link.
{
"status": 200,
"taskId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
"url": "https://cdn.finevoice.ai/output/result.mp3"
}
status | Meaning |
|---|
200 | Completed — result is ready |
202 | In progress — poll again |
All POST endpoints accept Content-Type: application/json.
POST /v1/audio/speech-synthesis
Authorization: Bearer YOUR_API_KEY
Content-Type: application/json
{
"voice": "james",
"text": "[happy] Hello! Welcome to FineVoice."
}
Error Responses
| HTTP Status | Meaning |
|---|
401 | Unauthorized — missing or invalid API key |
422 | Validation error — check your request body fields |
404 | Not found — resource or task does not exist |
Quick Start
See the Quick Start guide to generate your first audio output in under 5 minutes.
