Inworld AI

Inworld AI is a research lab and inference provider building the realtime voice layer for consumer-facing AI applications. Its platform combines first-party Realtime Text-to-Speech and Speech-to-Text models with an LLM router that spans 220+ models from OpenAI, Anthropic, Google, and others, all accessible through modular APIs or a single unified Realtime API over one WebSocket connection.

Inworld's Realtime TTS-2 is consistently top-ranked on the Artificial Analysis Speech Arena, offering sub-100ms time-to-first-byte, natural-language voice steering, text-based voice design, and voice cloning from just 15 seconds of audio across 200+ languages. The Realtime STT model adds built-in voice profiling, surfacing emotion, age, accent, and pitch signals per audio chunk, while the Realtime Router intelligently selects and fails over between LLMs with zero markup on provider rates.

The platform is built for developers and product teams shipping voice agents, AI companions, interactive games, language-learning tools, and customer support systems at scale, with SOC 2 Type II, HIPAA, and GDPR compliance built in for enterprise deployments.

Inworld AI uses a credit-based subscription model with a free On-Demand tier for evaluation and prototyping, including up to 70 minutes of TTS or 400 minutes of STT at no cost, with 100 custom voices and full Realtime API access under a commercial license.

Paid plans start with Creator at $25/month (up to 33% off base rates), Builder at $100/month (up to 40% off, workspace sharing), Developer at $300/month (up to 47% off, priority email support), and Growth at $1,500/month (up to 53% off, 30,000 custom voices, HIPAA and BAA add-ons). Realtime TTS-2 pricing ranges from $25 per million characters on-demand down to $12.50 on the Growth plan, with Realtime TTS-2 Flash starting at $15 and falling to $7.

Enterprise pricing is fully custom, with Realtime TTS-2 rates as low as $5 per million characters, price-match guarantees, SLAs, EU and India data residency, and a dedicated account manager. Unused subscription credits roll over for up to 3 months, and LLM usage through the Realtime Router is billed at provider cost with no markup.