xAI's family of large language models
xAI's family of large language models, used across the xAI API, Grok.com, iOS and Android apps, and Grok in X.
First-party xAI documentation; token-based pricing for the Grok 4 Fast API model. xAI’s broader models page also lists Grok models with text/image input and token pricing.
xAI’s official docs page for Grok 4 Fast publishes public API token pricing. The page lists $0.20 per 1M input tokens, $0.05 per 1M cached input tokens, and $0.50 per 1M output tokens, with the model presented as a Grok model in xAI’s official documentation.
xAI opened a Grok TTS API with five voices, inline controls for laughter and whispering, and multilingual streaming integrations that quickly landed in LiveKit and fal. Try it for voice products that need real-time playback, telephony formats, and hosted integration paths out of the box.
Vals published a benchmark pass for Grok 4.20 Beta showing gains on coding, math, multimodal, and Terminal Bench 2, alongside weaker legal-task results. Check task-level results before adopting it, especially if legal workflows matter more than headline benchmark gains.
xAI released Grok 4.20 Beta in the API with reasoning, non-reasoning, and multi-agent variants, a 2M-token window, and lower pricing than Grok 4. Test it for long-context and speed-sensitive workloads, but compare coding performance against top rivals on your own evals.
