Side-by-side comparison of pricing, context window, benchmarks, capabilities, and license. Data sourced from the Interestana AI Index, kept current as developers update their models.
Model A — xAI
Grok 4 is xAI’s flagship model, trained on the Colossus supercomputer cluster. Distinguished by real-time access to X (Twitter) data for current-events reasoning.
Model B — OpenAI
o3 is OpenAI’s flagship reasoning model, scaling deliberate test-time compute to solve novel mathematics and science problems that earlier LLMs could not.
| Property | Grok 4 | OpenAI o3 |
|---|---|---|
| Released | Apr 10, 2026 | Jan 31, 2026 |
| Developer | xAI | OpenAI |
| Type | multimodal | reasoning |
| License | proprietary | proprietary |
| Context window | 1,000,000 | 200,000 |
| Parameters | — | undisclosed |
| Input $/M tokens | $3.00 | $15.00 |
| Output $/M tokens | $15.00 | $60.00 |
Bold green values indicate the winner on that dimension where comparison is meaningful (lower price wins; bigger context wins; more open license wins; newer date wins).
No shared capabilities
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