# Inworld TTS 1.5 Max

> Inworld's highest-quality realtime TTS with <200ms latency, SSML pauses, emotion markups like [happy], and 15-language support.

- **Provider**: replicate
- **Model ID**: inworld/tts-1.5-max
- **Category**: tts_voice
- **Credits**: 24 per request
- **Pricing Type**: token_based

## API Endpoint

Base URL: https://api.core.today/v1

### Create Prediction
POST /predictions

### Get Status
GET /predictions/{job_id}

### Cancel
DELETE /predictions/{job_id}

## Authentication

Header: `X-API-Key: YOUR_API_KEY`

## Input Parameters

- `sample_rate` (integer, optional): Audio sample rate in Hz. (Default: `48000`; Options: `8000`, `16000`, `22050`, `24000`, `32000`, `44100`, `48000`)
- `voice_id` (string, optional): The voice to use. Use a preset voice name (e.g. 'Ashley', 'Dennis', 'Alex') or a custom cloned voice ID. (Default: `Ashley`)
- `speaking_rate` (number, optional): Speaking speed multiplier. Set to 0 for normal speed (1.0). (Default: `0`; Range: min: 0, max: 1.5)
- `temperature` (number, optional): Controls randomness when generating audio. Higher values produce more expressive results, lower values are more deterministic. Set to 0 to use the model default (1.1). (Default: `0`; Range: min: 0, max: 2)
- `audio_format` (string, optional): Output audio format. (Default: `mp3`; Options: `mp3`, `wav`, `ogg_opus`, `flac`)
- `text_normalization` (string, optional): Controls whether numbers, dates, and abbreviations are expanded before synthesis. 'auto' lets the model decide, 'on' always normalizes, 'off' reads text as-is. (Default: `auto`; Options: `auto`, `on`, `off`)
- `text` (string, **required**): The text to convert to speech. Maximum 2,000 characters. Supports SSML break tags for pauses (e.g. `<break time="1s" />`), emotion markups (e.g. `[happy]`, `[sad]`), and non-verbal vocalizations (e.g. `[laugh]`, `[sigh]`).

## Example Request

```json
{
  "model": "inworld/tts-1.5-max",
  "input": {
    "voice_id": "Ashley",
    "text": "Welcome to the future of voice AI. Inworld's text-to-speech technology brings natural, expressive speech to any application."
  }
}
```

## Response Format

```json
{
  "job_id": "abc123",
  "status": "pending",
  "provider": "replicate",
  "model": "black-forest-labs/flux-schnell",
  "created_at": "2026-01-01T00:00:00Z",
  "result": null,
  "error": null
}
```

Status values: `pending`, `processing`, `completed`, `failed`, `cancelled`

## Usage Flow

1. POST /predictions with model and input → receive job_id
2. Poll GET /predictions/{job_id} until status is `completed` or `failed`
3. Result contains output URL(s) or data

## Output Type

url

## Tags

text-to-speech, tts, audio, voice-synthesis, inworld, real-time, emotion-control, multilingual

## Documentation

https://replicate.com/inworld/tts-1.5-max


## Token Pricing

- Input: 0.02325 credits/token
- Output: 0.02325 credits/token