GPT-6 Astra vs Kimi K3
GPT-6 Astra (OpenAI) and Kimi K3 (Moonshot) compared on benchmarks, pricing, context window, and use-case rankings.
- GPT-6 Astra leads on overall intelligence (ECI 169 vs 158).
- Kimi K3 is cheaper on input tokens — $2.55 vs $10.00 per 1M.
- GPT-6 Astra has a larger context window (1.1M vs 1M tokens).
- Kimi K3 ranks higher for coding (97th vs 95th percentile).
| Attribute | GPT-6 Astra | Kimi K3 |
|---|---|---|
| Scores | ||
| Intelligence (ECI) | 169 | 158 |
| Coding | 95 | 97 |
| Math | 96 | 81 |
| Reasoning & Knowledge | 99 | 73 |
| Agentic & Tools | 96 | 80 |
| Specifications | ||
| Developer | OpenAI | Moonshot |
| Family | GPT | Kimi |
| Released | Sep 3, 2026 | Jul 16, 2026 |
| Parameters | — | 2.8T |
| Availability | API access | Open weights (non-commercial) |
| Context window | 1.1M | 1M |
| Price — $/M input | $10.00 | $2.55 |
| Price — $/M output | $50.00 | $12.75 |
| Inputs | file, image, text | text, image, video |
| Outputs | text | text |
| Benchmarks | ||
| AIME 2024/2025 | 100% | 97% |
| APEX | 47% | 39% |
| ARC-AGI | 99% | 95% |
| ARC-AGI-2 | 95% | 60% |
| GPQA Diamond | 96% | 93% |
| Humanity's Last Exam | 55% | 47% |
| SciCode | 56% | 60% |
| SimpleQA Verified | 76% | 51% |
| WebDev Arena | 1797 | 1674 |
| WeirdML | 93% | 83% |
| SimpleBench | — | 61% |
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 Kimi K3?
On Epoch AI's Capabilities Index, GPT-6 Astra scores higher (169) than Kimi K3 (158). 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 Kimi K3?
Kimi K3 is cheaper on input tokens at $2.55 per million, versus $10.00 (representative OpenRouter pricing).
Which has a larger context window, GPT-6 Astra or Kimi K3?
GPT-6 Astra supports up to 1.1M tokens, compared with 1M for the other.
Which is better for coding, GPT-6 Astra or Kimi K3?
Across coding benchmarks like SWE-bench Verified and Terminal-Bench, Kimi K3 ranks higher — 97th vs 95th 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.