Audience
Developers seeking to build low-latency voice agents that hold real-time speech conversations and use tools during interactions
About Grok Voice Think Fast 2.0
Grok Voice Think Fast 2.0 is xAI’s flagship voice model for building real-time assistants, phone agents, and interactive voice systems that stream audio and text bidirectionally over WebSocket. Developers can configure system instructions, high or no reasoning effort, built-in or custom voices, automatic server-side voice activity detection, silence duration, idle re-engagement, playback speed, and session resumption after temporary disconnects. It accepts PCM, G.711 μ-law, G.711 A-law, and Opus audio through JSON or raw binary frames, with configurable PCM sample rates from telephone quality to 48 kHz. It supports more than 20 languages with native-quality accents, automatic language detection, natural responses in the speaker’s language, and seamless code-switching. Language hints and up to 100 key terms improve transcription of regional speech, names, products, codes, addresses, and specialized terminology, while pronunciation replacements correct spoken output.
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Company Information
SpaceXSI
Founded: 2023
United States
docs.x.ai/developers/model-capabilities/audio/speech-to-speech
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Product Details
Platforms Supported
Cloud
Training
Documentation
Support
Online
Grok Voice Think Fast 2.0 Frequently Asked Questions
Q: What kinds of users and organization types does Grok Voice Think Fast 2.0 work with?
Grok Voice Think Fast 2.0 works with these users and organization types: Mid Size Business, Small Business, Enterprise, Freelance, Nonprofit, Government, and Startup.
Q: What languages does Grok Voice Think Fast 2.0 support in their product?
Grok Voice Think Fast 2.0 supports these languages: English.
Q: What kind of support options does Grok Voice Think Fast 2.0 offer?
Grok Voice Think Fast 2.0 offers support via online.
Q: What other applications or services does Grok Voice Think Fast 2.0 integrate with?
Grok Voice Think Fast 2.0 integrates with: Vercel AI Gateway, Grok Voice Agent Builder, Grok Voice Agent, and Grok.
Q: Does Grok Voice Think Fast 2.0 have an API?
Yes, Grok Voice Think Fast 2.0 has an API.
Q: What type of training does Grok Voice Think Fast 2.0 provide?
Grok Voice Think Fast 2.0 provides training in the form of documentation.
