GPT-6 Astra vs Mistral Medium 3.5
GPT-6 Astra (OpenAI) and Mistral Medium 3.5 (Mistral AI) compared on benchmarks, pricing, context window, and use-case rankings.
- GPT-6 Astra leads on overall intelligence (ECI 169 vs 141).
- Mistral Medium 3.5 is cheaper on input tokens — $1.50 vs $10.00 per 1M.
- GPT-6 Astra has a larger context window (1.1M vs 262K tokens).
- GPT-6 Astra ranks higher for coding (95th vs 18th percentile).
| Attribute | GPT-6 Astra | Mistral Medium 3.5 |
|---|---|---|
| Scores | ||
| Intelligence (ECI) | 169 | 141 |
| Coding | 95 | 18 |
| Math | 96 | — |
| Reasoning & Knowledge | 99 | 18 |
| Agentic & Tools | 96 | 75 |
| Specifications | ||
| Developer | OpenAI | Mistral AI |
| Family | GPT | Mistral |
| Released | Sep 3, 2026 | Apr 28, 2026 |
| Parameters | — | — |
| Availability | API access | Open weights (restricted use) |
| Context window | 1.1M | 262K |
| Price — $/M input | $10.00 | $1.50 |
| Price — $/M output | $50.00 | $7.50 |
| Inputs | file, image, text | text, image, file |
| Outputs | text | text |
| Benchmarks | ||
| AIME 2024/2025 | 100% | — |
| APEX | 47% | — |
| ARC-AGI | 99% | — |
| ARC-AGI-2 | 95% | — |
| GPQA Diamond | 96% | 75% |
| Humanity's Last Exam | 55% | 14% |
| SciCode | 56% | 40% |
| SimpleQA Verified | 76% | — |
| WebDev Arena | 1797 | 1265 |
| WeirdML | 93% | 44% |
| τ²-bench | — | 94% |
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 Mistral Medium 3.5?
On Epoch AI's Capabilities Index, GPT-6 Astra scores higher (169) than Mistral Medium 3.5 (141). The right pick depends on your task — compare their coding, math, and reasoning scores in the table above.
Which is cheaper, GPT-6 Astra or Mistral Medium 3.5?
Mistral Medium 3.5 is cheaper on input tokens at $1.50 per million, versus $10.00 (representative OpenRouter pricing).
Which has a larger context window, GPT-6 Astra or Mistral Medium 3.5?
GPT-6 Astra supports up to 1.1M tokens, compared with 262K for the other.
Which is better for coding, GPT-6 Astra or Mistral Medium 3.5?
Across coding benchmarks like SWE-bench Verified and Terminal-Bench, GPT-6 Astra ranks higher — 95th vs 18th 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.