Grok 4.3 (Reasoning)
by xAI
Grok 4.3 (Reasoning) is a reasoning model from xAI, released on May 6, 2026. It has a 1M-token context window. API pricing is $1.25 per 1M input tokens and $2.5 per 1M output tokens.
Grok 4.3 is xAI's newest flagship general-purpose model. xAI describes it as the most intelligent and fastest model it has built, with a 1 million token context window, reasoning support, function calling, structured outputs, prompt caching, and industry-leading non-hallucination, agentic tool calling, and instruction-following capabilities.
Key specs
| Provider | xAI |
|---|---|
| Release date | 2026-05-06 |
| License | proprietary |
| Context window | 1M tokens |
| Input price | $1.25 / 1M tokens |
| Output price | $2.5 / 1M tokens |
| Intelligence Score | 22 |
Quick answers
What is the context window of Grok 4.3 (Reasoning)?
Grok 4.3 (Reasoning) has a context window of 1M tokens.
How much does Grok 4.3 (Reasoning) cost?
Grok 4.3 (Reasoning) costs $1.25 per 1M input tokens and $2.5 per 1M output tokens through the API.
Is Grok 4.3 (Reasoning) open source?
No. Grok 4.3 (Reasoning) is a proprietary model from xAI (proprietary license).
When was Grok 4.3 (Reasoning) released?
xAI released Grok 4.3 (Reasoning) on May 6, 2026.
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