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GPT-6 Astra vs Kimi K3

GPT-6 Astra leads the LLM Stats Score 60.7 to 53.8. Kimi K3 is 3.3x cheaper per token.

OpenAI · Moonshot AI · Updated for 2026

Which is better?

GPT-6 Astra leads the overall LLM Stats Score 60.7 to 53.8, ranking #1 overall.

In the 4 individual benchmarks reported for both models, GPT-6 Astra wins 4; this is a narrower head-to-head signal than the composite indexes.

On price, Kimi K3 is roughly 3.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-6 Astra also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.

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

Choose GPT-6 Astra

  • overall performance matters — it scores 60.7 and ranks #1 on LLM Stats
  • your work emphasizes reasoning and agents — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 4 of 4 exact shared results
  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose Kimi K3

  • cost matters — it's about 3.3x cheaper per token
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Core performance indexes
60.7
#1
53.8
#8
58.7
#1
52.6
#8
49.0
#1
43.4
#5
46.4
#1
39.1
#8
Cost, coverage & limits
Benchmark wins
4 of 4
0 of 4
Input price
$10.00 / M
$3.00 / M
Output price
$50.00 / M
$15.00 / M
Context window
1,050,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
GPT-6 Astra
Kimi K3
35.3#42
40.6#11
41.5#1
37.7#4
36.6#1
34.1#3
38.6#3
39.1#1
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

22 reported for GPT-6 Astra · 31 for Kimi K3

4 shared

GPT-6 Astra outperforms in 4 benchmarks (AutomationBench, BrowseComp, DeepSWE 1.1, GPQA), while Kimi K3 is better at 0 benchmarks.

GPT-6 Astra significantly outperforms across most benchmarks.

Fri Sep 04 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Kimi K3 costs less

For input processing, GPT-6 Astra ($10.00/1M tokens) is 3.3x more expensive than Kimi K3 ($3.00/1M tokens).

For output processing, GPT-6 Astra ($50.00/1M tokens) is 3.3x more expensive than Kimi K3 ($15.00/1M tokens).

In conclusion, GPT-6 Astra is more expensive than Kimi K3.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Sep 04 2026 • llm-stats.com
OpenAI
GPT-6 Astra
Input tokens$10.00
Output tokens$50.00
Best providerOpenAI
Moonshot AI
Kimi K3
Input tokens$3.00
Output tokens$15.00
Best providerFireworks
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

GPT-6 Astra accepts 1,050,000 input tokens compared to Kimi K3's 1,048,576 tokens. Kimi K3 can generate longer responses up to 1,048,576 tokens, while GPT-6 Astra is limited to 128,000 tokens.

OpenAI
GPT-6 Astra
Input1,050,000 tokens
Output128,000 tokens
Moonshot AI
Kimi K3
Input1,048,576 tokens
Output1,048,576 tokens
Fri Sep 04 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both GPT-6 Astra and Kimi K3 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

GPT-6 Astra

Text
Images
Audio
Video

Kimi K3

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-6 Astra is licensed under a proprietary license, while Kimi K3 uses Kimi K3 License.

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

GPT-6 Astra

Proprietary

Closed source

Kimi K3

Kimi K3 License

Open weights

Release Timeline

When each model was launched

GPT-6 Astra was released on 2026-09-03, while Kimi K3 was released on 2026-07-16.

GPT-6 Astra is 2 months newer than Kimi K3.

GPT-6 Astra

Sep 3, 2026

0 days ago

1mo newer
Kimi K3

Jul 16, 2026

1 months ago

Knowledge Cutoff

When training data ends

GPT-6 Astra has a documented knowledge cutoff of 2026-04-30, while Kimi K3'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 K3's cutoff date.

GPT-6 Astra

Apr 2026

Kimi K3

Provider Availability

GPT-6 Astra is available from OpenAI. Kimi K3 is available from Fireworks, Moonshot AI, Novita, Together.

GPT-6 Astra

openai logo
OpenAI
Input Price:Input: $10.00/1MOutput Price:Output: $50.00/1M

Kimi K3

fireworks logo
Fireworks
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
moonshot logo
Unknown Organization
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
novita logo
Novita
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
together logo
Together
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against GPT-6 Astra and Kimi K3 side-by-side, then vote on the output you prefer.

GPT-6 Astra
✓ Preferred
Kimi K3
Open in Playground

FAQ

Common questions about GPT-6 Astra vs Kimi K3.

Which is better, GPT-6 Astra or Kimi K3?

GPT-6 Astra leads the LLM Stats Score 60.7 to 53.8. GPT-6 Astra is made by OpenAI and Kimi K3 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 K3 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 K3 scores MathVision: 97.8%, DeepSearchQA: 95.0%, GPQA: 93.5%, CharXiv-R: 91.3%, BrowseComp: 91.2%.

Is GPT-6 Astra cheaper than Kimi K3?

Kimi K3 is 3.3x cheaper for input tokens. GPT-6 Astra costs $10.00/M input and $50.00/M output via openai. Kimi K3 costs $3.00/M input and $15.00/M output via fireworks.

What are the context window sizes for GPT-6 Astra and Kimi K3?

GPT-6 Astra supports 1.1M tokens and Kimi K3 supports 1.0M 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 K3?

Key differences include LLM Stats Score (60.7 vs 53.8), context window (1.1M vs 1.0M), input pricing ($10.00 vs $3.00/M), licensing (Proprietary vs Kimi K3 License). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-6 Astra and Kimi K3?

GPT-6 Astra is developed by OpenAI and Kimi K3 is developed by Moonshot AI.