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GPT-6 Astra vs Kimi K2-Instruct-0905

GPT-6 Astra leads the LLM Stats Score 58.3 to 21.5.

OpenAI · Moonshot AI · Updated for 2026

Which is better?

GPT-6 Astra leads the overall LLM Stats Score 58.3 to 21.5, ranking #3 overall.

In the 1 individual benchmarks reported for both models, GPT-6 Astra wins 1; this is a narrower head-to-head signal than the composite indexes.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose GPT-6 Astra

  • overall performance matters — it scores 58.3 and ranks #3 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results
  • you want the most recent training data — it shipped Sep 2026

Choose Kimi K2-Instruct-0905

  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

GPT-6 Astra
OpenAI
Kimi K2-Instruct-0905
Moonshot AI
Core performance indexes
LLM Stats Score
58.3
#3
21.5
#202
Reasoning
56.7
#3
21.8
#192
Coding
47.8
#3
9.6
#184
Agents
44.9
#2
-4.2
#197
Cost, coverage & limits
Benchmark wins
1 of 1
0 of 1
Input price
$10.00 / M
— / M
Output price
$50.00 / M
— / M
Context window
1,050,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
GPT-6 Astra
Kimi K2-Instruct-0905
Math
33.5#56
21.5#150
Tool use
35.2#1
6.4#156
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

22 reported for GPT-6 Astra · 29 for Kimi K2-Instruct-0905

1 shared

GPT-6 Astra outperforms in 1 benchmarks (GPQA), while Kimi K2-Instruct-0905 is better at 0 benchmarks.

GPT-6 Astra significantly outperforms across most benchmarks.

Sat Oct 10 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only GPT-6 Astra specifies input context (1,050,000 tokens). Only GPT-6 Astra specifies output context (128,000 tokens).

OpenAI
GPT-6 Astra
Input1,050,000 tokens
Output128,000 tokens
Moonshot AI
Kimi K2-Instruct-0905
Input- tokens
Output- tokens
Sat Oct 10 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

GPT-6 Astra supports multimodal inputs, whereas Kimi K2-Instruct-0905 does not.

GPT-6 Astra can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-6 Astra

Text
Images
Audio
Video

Kimi K2-Instruct-0905

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-6 Astra is licensed under a proprietary license, while Kimi K2-Instruct-0905 uses MIT.

License differences may affect how you can use these models in commercial or open-source projects.

GPT-6 Astra

Proprietary

Closed source

Kimi K2-Instruct-0905

MIT

Open weights

Release Timeline

When each model was launched

GPT-6 Astra was released on 2026-09-04, while Kimi K2-Instruct-0905 was released on 2025-09-05.

GPT-6 Astra is 12 months newer than Kimi K2-Instruct-0905.

GPT-6 Astra

Sep 4, 2026

1 months ago

12mo newer
Kimi K2-Instruct-0905

Sep 5, 2025

1.1 years ago

Knowledge Cutoff

When training data ends

GPT-6 Astra has a documented knowledge cutoff of 2026-04-30, while Kimi K2-Instruct-0905's cutoff date is not specified.

We can confirm GPT-6 Astra's training data extends to 2026-04-30, but cannot make a direct comparison without Kimi K2-Instruct-0905's cutoff date.

GPT-6 Astra

Apr 2026

Kimi K2-Instruct-0905

—

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against GPT-6 Astra and Kimi K2-Instruct-0905 side-by-side, then vote on the output you prefer.

GPT-6 Astra
✓ Preferred
Kimi K2-Instruct-0905
Open in Playground

FAQ

Common questions about GPT-6 Astra vs Kimi K2-Instruct-0905.

Which is better, GPT-6 Astra or Kimi K2-Instruct-0905?

GPT-6 Astra leads the LLM Stats Score 58.3 to 21.5. GPT-6 Astra is made by OpenAI and Kimi K2-Instruct-0905 is made by Moonshot AI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GPT-6 Astra compare to Kimi K2-Instruct-0905 in benchmarks?

GPT-6 Astra scores ExploitBench: 100.0%, ARC-AGI-3: 99.9%, ARC-AGI: 98.5%, FrontierMath Tier 4 (v2): 97.6%, GPQA: 96.0%. Kimi K2-Instruct-0905 scores MATH-500: 97.4%, MMLU-Redux: 92.7%, IFEval: 89.8%, AutoLogi: 89.5%, MMLU: 89.5%.

What are the context window sizes for GPT-6 Astra and Kimi K2-Instruct-0905?

GPT-6 Astra supports 1.1M tokens and Kimi K2-Instruct-0905 supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-6 Astra and Kimi K2-Instruct-0905?

Key differences include LLM Stats Score (58.3 vs 21.5), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-6 Astra and Kimi K2-Instruct-0905?

GPT-6 Astra is developed by OpenAI and Kimi K2-Instruct-0905 is developed by Moonshot AI.

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