AI Text-to-Speech API docs

Convert text to natural-sounding speech. Multiple voices, languages, speed control, and audio format options.

Authentication

All AI Text-to-Speech API requests authenticate via two headers. Get your API key from your RapidAPI dashboard after subscribing on the Basic (free) tier or higher.

X-RapidAPI-Key: YOUR_API_KEY
X-RapidAPI-Host: ai-tts-by-helix-api.p.rapidapi.com

Base URL

https://ai-tts-by-helix-api.p.rapidapi.com

Endpoints

POST
/speak

Convert text to speech audio

GET
/voices

List available voices

Code Examples

Python

import requests

url = "https://ai-tts-by-helix-api.p.rapidapi.com/speak"
headers = {
    "X-RapidAPI-Key": "YOUR_API_KEY",
    "X-RapidAPI-Host": "ai-tts-by-helix-api.p.rapidapi.com",
}

response = requests.post(url, headers=headers)
print(response.json())

JavaScript

const response = await fetch(
  "https://ai-tts-by-helix-api.p.rapidapi.com/speak",
  {
    method: "POST",
    headers: {
      "X-RapidAPI-Key": "YOUR_API_KEY",
      "X-RapidAPI-Host": "ai-tts-by-helix-api.p.rapidapi.com"
    }
  }
);
const data = await response.json();

cURL

curl -X POST "https://ai-tts-by-helix-api.p.rapidapi.com/speak" \
  -H "X-RapidAPI-Key: YOUR_API_KEY" \
  -H "X-RapidAPI-Host: ai-tts-by-helix-api.p.rapidapi.com"

Response Format

All endpoints return JSON in this consistent envelope:

{
  "status": "ok",
  "data": { /* endpoint-specific payload */ },
  "meta": {
    "cached": false,
    "latency_ms": 142,
    "request_id": "req_abc123"
  },
  "timestamp": "2026-05-21T12:00:00Z"
}

Error Codes

HTTPCodeMeaning
400BAD_REQUESTMissing or invalid parameter
401UNAUTHORIZEDInvalid or missing API key
403FORBIDDENYour plan doesn't include this endpoint
429RATE_LIMIT_EXCEEDEDToo many requests — back off and retry
500INTERNAL_ERRORSomething went wrong on our side
503UPSTREAM_UNAVAILABLEA third-party data source is down

Common Use Cases

Podcast generation
Accessibility tools
E-learning narration
IVR systems
Audiobook creation
Voice notification alerts
Meditation app narration
News article read-aloud
In-app voice assistant
Language learning pronunciation
Video voiceover generation
Automated phone announcements
Children's story narration
Product tour audio guides
Public transit announcements
Museum audio guide
Recipe step-by-step narration
Fitness workout audio coaching
Customer onboarding voice walkthrough
Multilingual chatbot voice replies

Related APIs

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