name: inworld
description: "Inworld TTS API. Covers voice cloning, audio markups, timestamps. Keywords: text-to-speech, visemes."
version: "1.5"
release_date: "2026-01-21"

Inworld AI

Text-to-Speech platform with voice cloning, audio markups, and timestamp alignment.

Quick Navigation

When to Use

• Text-to-speech audio generation
• Voice cloning from 5-15 seconds of audio
• Emotion-controlled speech ([happy], [sad], etc.)
• Word/phoneme timestamps for lip sync
• Custom pronunciation with IPA

Models

Minimal Example

import requests, base64, os

response = requests.post(
    "https://api.inworld.ai/tts/v1/voice",
    headers={"Authorization": f"Basic {os.getenv('INWORLD_API_KEY')}"},
    json={"text": "Hello!", "voiceId": "Ashley", "modelId": "inworld-tts-1.5-max"}
)
audio = base64.b64decode(response.json()['audioContent'])

Key Features

• 15 languages — en, zh, ja, ko, ru, it, es, pt, fr, de, pl, nl, hi, he, ar
• Instant cloning — 5-15 seconds audio, no training
• Audio markups — [happy], [laughing], [sigh] (English only)
• Timestamps — word, phoneme, viseme timing for lip sync
• Streaming — /voice:stream endpoint

Prohibitions

• Audio markups work only in English
• Use ONE emotion markup at text beginning
• Match voice language to text language
• Instant cloning may not work for children's voices or unique accents

Links

• Docs: https://docs.inworld.ai/docs/tts/tts
• Platform: https://platform.inworld.ai/