As of: 2026-11-13 13:49 CET.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/m/inworld-tts-2/

# Inworld Realtime TTS-2 / TTS-2 Flash

Inworld AI, Inworld TTS family. Status: current. Type: speech and audio. Released: 2026-08-31.

## How to call it

| Provider | Model id | Endpoint | Docs |
|---|---|---|---|
| Inworld API | `inworld-tts-2` | https://api.inworld.ai/tts/v1/voice | https://docs.inworld.ai/tts/tts-models |
| Cloudflare Workers AI |  |  | https://developers.cloudflare.com/ai/models/inworld/tts-2/ |

## Pricing

- Per 1M characters: $25
- Unit as published: USD per 1M characters PAYG for TTS-2 ($15 for TTS-2 Flash); plan rates down to $12.50/$7, enterprise from $5
- Source: https://inworld.ai/pricing
- Last checked: 2026-09-29

## Specs

- Input: text, audio
- Output: audio
- Context window: not published
- Max output: not published
- Open weights: no
- Licence: proprietary

## Where it stands

- Newer speech and audio models in the registry since its release: 30. The 5 newest:
  - NVIDIA Nemotron 3.5 Transcribe (30B-A4B) (2026-10-28) https://postcutoff.com/m/nemotron-3-5-transcribe/
  - Hy-SimulMT-30B-A3B (2026-10-22) https://postcutoff.com/m/hy-simulmt-30b-a3b/
  - Eleven Realtime v1 Max / Mini (2026-10-20) https://postcutoff.com/m/eleven-realtime-v1-max/
  - Voxtral Mini Transcribe 3 (+ Mini Transcribe Realtime 3) (2026-10-20) https://postcutoff.com/m/voxtral-mini-transcribe-3/
  - Voxtral Small Transcribe 3 (2026-10-20) https://postcutoff.com/m/voxtral-small-transcribe-3/
- Closed weights; access is hosted only.

## What stands out

- Closed-loop, audio-aware delivery: Conditions on the actual audio of prior turns (user tone, pacing, emotion), not just transcripts, and takes plain-English voice direction; delivery modes STABLE/BALANCED/CREATIVE. Source: https://inworld.ai/blog/realtime-tts-2
- Cross-lingual identity in 100+ languages: One voice holds identity while switching language on the fly; cloning from 5-15 s reference or voice design from a text description. Source: https://inworld.ai/blog/realtime-tts-2
- Flash variant ~20 ms TTFB: TTS-2 Flash: ~20 ms TTFB, ~5x faster than inworld-tts-2 (docs); TTS-2 median TTFA under 200 ms. Source: https://docs.inworld.ai/tts/tts-models

## Notes

Research preview 2026-05-05, GA 2026-08-31. Inworld claimed #1 on Artificial Analysis Speech Arena; on 2026-09-29 AA shows it #5 (Elo 1244) behind Eleven v4, Sonic 3.6, Gemini 3.8 Flash TTS, Qwen-Audio-3.0-TTS-Plus. Docs say 200+ languages vs 100+ in blog. TTS-1..1.5 discontinued 2026-06-15 (auto-routed). Flash model id not verified. Max 2,000 chars/request.

Sources: https://inworld.ai/blog/realtime-tts-2 , https://docs.inworld.ai/tts/tts-models , https://inworld.ai/pricing

Model page: https://postcutoff.com/m/inworld-tts-2/