Text-to-SpeechAnonymized

Inworld TTS-1.5 Max

Inworld TTS-1.5 Max is the highest-ranked text-to-speech model globally, delivering ultra-low latency, expressive speech, and zero data retention for production-grade voice AI.

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What is Inworld TTS-1.5 Max?

Inworld TTS-1.5 Max is a state-of-the-art text-to-speech model developed by Inworld AI, released in January 2026. It delivers ultra-realistic, context-aware speech with sub-250ms P90 latency, supports over 200 languages, and leads independent benchmarks in voice quality with an Elo of 1,197–1,236.

Use Inworld TTS-1.5 Max privately on Venice

On Venice, Inworld TTS-1.5 Max runs under an anonymized privacy tier—your text prompts are never stored, profiled, or used for training. This means developers get enterprise-grade voice synthesis with full data sovereignty, ideal for sensitive applications. The model’s API-first design integrates seamlessly into privacy-conscious workflows without compromising on speed or expressiveness.

Anonymized
No prompt training
TEE · hardware enclave
End-to-end encrypted

What can Inworld TTS-1.5 Max do?

Strengths
  • Ranked #1 in global speech benchmarks (Artificial Analysis Speech Arena), outperforming ElevenLabs and Gemini Flash.
  • Ultra-low latency (<250ms P90) ideal for real-time voice agents and interactive media.
  • Supports over 200 languages and locales with high multilingual fidelity.
  • High-quality instant voice cloning via API with only 5–15 seconds of reference audio.
  • 30% more expressive and 40% fewer word errors than prior generations.
Limitations
  • API-only access — no consumer interface, studio, or free tier.
  • Proprietary and closed model — cannot be self-hosted or fine-tuned.
  • Higher cost per character than budget models like Kokoro TTS.

Sample outputs

Generated on Venice with our standard prompt suite — the same scripts we run through every model of this type, so you can judge it like-for-like.

Narration

On Venice, your prompts are processed privately and never stored, profiled, or used to train anyone's model.

Conversational

Wait — so I can run a private voice model with zero data retention, and pay only for what I use? That's genuinely useful.

Expressive range

Three… two… one… liftoff! The rocket roared into the night sky as the crowd erupted in cheers.

Compare every speech model on these scripts

How to use Inworld TTS-1.5 Max via API

Venice exposes an OpenAI-compatible API. Swap your base URL and call tts-inworld-1-5-max.

curl https://api.venice.ai/api/v1/audio/speech \
  -H "Authorization: Bearer $VENICE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "tts-inworld-1-5-max",
    "input": "On Venice, your prompts are processed privately.",
    "voice": "af_sky",
    "response_format": "mp3"
  }' --output speech.mp3

Specifications

MakerInworld AI
ReleasedJanuary 21, 2026
ModalityText-to-speech
Supported languages200+
Latency<250ms P90, ~200ms median
Voice cloningYes — instant via API
Open weightsNo — proprietary
Privacy on VeniceAnonymized — prompts not stored
Available on Venice sinceApr 2026
LicenseProprietary

Pricing

Billed per character on Venice: $12.50 per 1M characters of synthesized speech.

Characters / 1M
$12.50

New Venice accounts include a free daily allowance and 500 welcome credits — no credit card required.

Inworld TTS-1.5 Max vs alternatives

ModelPrice (Venice)LatencyVoice cloningOpen weights
Inworld TTS-1.5 Max$12.50 / 1M chars<250ms P90YesNo
ElevenLabs Turbo v2.5$62.50 / 1M chars<100msYesNo
Gemini 3.1 Flash TTS$187.50 / 1M chars~200msYesNo
Kokoro Text to Speech$3.50 / 1M charsYesYes

Top-ranked TTS model with best-in-class expressiveness and multilingual support.

What is Inworld TTS-1.5 Max good for?

  • Real-time conversational AI agents requiring natural, low-latency voice responses.
  • Multilingual customer service bots with expressive, human-like delivery.
  • Interactive gaming NPCs with dynamic, context-aware dialogue.
  • Live translation and dubbing for video content.
  • Voice cloning for personalized audio experiences in apps and media.

Prompting tips

  • Use natural language steering to control tone, pacing, and emotion in the generated speech.
  • For cloning, provide clean, 10-second reference clips in the target language for best results.
  • Leverage streaming WebSocket endpoints for real-time agent applications to minimize perceived latency.

Version history

Inworld Realtime TTS
2024

Initial generation model

Inworld TTS-1.5 Max
2026-01

CurrentCurrent flagship — faster, more expressive, top-ranked

Frequently asked questions

Inworld TTS-1.5 Max is a high-performance text-to-speech model released in January 2026 by Inworld AI. It delivers expressive, low-latency speech synthesis with support for over 200 languages and is ranked #1 in independent voice quality benchmarks.

On Venice, Inworld TTS-1.5 Max costs $12.50 per 1 million characters of synthesized speech, billed per character with no subscription required.

No. Inworld TTS-1.5 Max is a proprietary model developed by Inworld AI. It is not open source or freely available for self-hosting. Access is via API only.

Yes. The model supports instant voice cloning via API using just 5–15 seconds of reference audio. This enables personalized voices for agents, avatars, and media applications.

The model achieves P90 time-to-first-audio under 250ms and a median latency of approximately 200ms, making it ideal for real-time conversational AI and interactive applications.

Inworld TTS-1.5 Max ranks higher in voice quality benchmarks and is more cost-effective, while ElevenLabs offers slightly lower latency and more granular emotional control. For pure quality and multilingual use, Inworld leads; for emotion steering, ElevenLabs has an edge.

Yes. On Venice, your text prompts are anonymized and not stored, profiled, or used for training. This ensures full privacy and data sovereignty for sensitive deployments.

The model supports over 200 languages and locales, making it one of the most comprehensive multilingual TTS systems available, ideal for global applications.

Related models

Run Inworld TTS-1.5 Max privately.

No prompt logging. No data used for training. Free to start — no credit card.

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