GPT-6 Astra vs Grok 4 Fast
GPT-6 Astra (OpenAI) and Grok 4 Fast (xAI) compared on benchmarks, pricing, context window, and use-case rankings.
- GPT-6 Astra leads on overall intelligence (ECI 169 vs 144).
- GPT-6 Astra ranks higher for coding (95th vs 37th percentile).
| Attribute | GPT-6 Astra | Grok 4 Fast |
|---|---|---|
| Scores | ||
| Intelligence (ECI) | 169 | 144 |
| Coding | 95 | 37 |
| Math | 96 | 48 |
| Reasoning & Knowledge | 99 | 27 |
| Agentic & Tools | 96 | 19 |
| Specifications | ||
| Developer | OpenAI | xAI |
| Family | GPT | Grok |
| Released | Sep 3, 2026 | Sep 19, 2025 |
| Parameters | — | — |
| Availability | API access | API access |
| Context window | 1.1M | — |
| Price — $/M input | $10.00 | — |
| Price — $/M output | $50.00 | — |
| Inputs | file, image, text | — |
| Outputs | text | — |
| Benchmarks | ||
| AIME 2024/2025 | 100% | 90% |
| APEX | 47% | — |
| ARC-AGI | 99% | 49% |
| ARC-AGI-2 | 95% | 5% |
| GPQA Diamond | 96% | 85% |
| Humanity's Last Exam | 55% | 19% |
| SciCode | 56% | 44% |
| SimpleQA Verified | 76% | — |
| WebDev Arena | 1797 | 1149 |
| WeirdML | 93% | 43% |
| LiveCodeBench | — | 83% |
| MMLU-Pro | — | 85% |
| τ²-bench | — | 66% |
Use-case scores are 0–100 percentile composites across each area’s benchmarks, ranked against every model from the past year. Highlighted cells lead each row. Open a model for the full picture.
Frequently asked questions
Is GPT-6 Astra better than Grok 4 Fast?
On Epoch AI's Capabilities Index, GPT-6 Astra scores higher (169) than Grok 4 Fast (144). The right pick depends on your task — compare their coding, math, and reasoning scores in the table above.
Which is better for coding, GPT-6 Astra or Grok 4 Fast?
Across coding benchmarks like SWE-bench Verified and Terminal-Bench, GPT-6 Astra ranks higher — 95th vs 37th percentile among the models tracked on Model Beat.
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Benchmarks & model data from Epoch AI (CC BY); pricing & specs from OpenRouter. ECI = Epoch Capabilities Index.