Grok 4.20 0309 (Reasoning)
Analysis Summary
Grok 4.20 0309 in reasoning mode is a strong performer from xAI's March 2026 release. Its agentic index of 68.7 places it in the top tier for autonomous task execution, and its instruction-following score of 0.829 is among the best in the field. GPQA of 0.885 and HLE of 0.30 confirm deep reasoning capability, while terminalbench of 0.409 and tau2 of 0.965 show reliable tool use and task completion.
For businesses, this model is well-suited to agentic pipelines, complex multi-step reasoning, software engineering assistance, and workflows requiring precise instruction adherence. The long-context reliability score of 0.59 is good, supporting document-heavy tasks. Its intelligence index of 36.5 is strong but sits below the very top frontier models, so for the most demanding reasoning tasks, a higher-tier model may still be preferred.
At $2 input and $6 output per million tokens, pricing is reasonable for the capability level, particularly given the agentic and instruction-following strengths. Teams building autonomous agents or needing reliable tool use at a mid-tier price point will find this a compelling option.
Assessed June 30, 2026
Editorial notes
Grok 4.20 0309 (Reasoning) from xAI delivers strong agentic performance with an index of 68.7, excellent instruction-following at 0.83, and high GPQA and HLE scores, making it a capable choice for complex reasoning and autonomous workflows at a competitive price point.
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Performance Profile
How Grok 4.20 0309 (Reasoning) compares
Grok 4.20 0309 (Reasoning) ranks #47 of 385 AI models we track for overall intelligence, #21 of 293 for agentic tasks. At $2.00 per million input tokens it is cheaper than 17% of comparable models.
Benchmark Scores
Intelligence
Technical
Content
Benchmark data from Artificial Analysis and Hugging Face
How does Grok 4.20 0309 (Reasoning) stack up?
Compare side-by-side with other professional models.
Model Information
| Provider | xAI |
| Release Date | March 10, 2026 |
| Status | Active |
Pricing
| Token Type | Cost per 1M tokens | Cost per 1K tokens |
|---|---|---|
| Input | $2.00 | $0.002000 |
| Output | $6.00 | $0.006000 |
Leaderboard Categories
Frequently asked questions about Grok 4.20 0309 (Reasoning)
How much does Grok 4.20 0309 (Reasoning) cost?
Grok 4.20 0309 (Reasoning) costs $2.00 per million input tokens and $6.00 per million output tokens.
Who created Grok 4.20 0309 (Reasoning)?
Grok 4.20 0309 (Reasoning) is developed by xAI and was released on March 10, 2026.
