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GPT-5.6 Terra vs Kimi K3

GPT-5.6 Terra and Kimi K3 are closely matched at 50.8 and 53.1 on the LLM Stats Score. GPT-5.6 Terra is 1.3x cheaper per token.

OpenAI · Moonshot AI · Updated for 2026

Which is better?

GPT-5.6 Terra and Kimi K3 are closely matched on the overall LLM Stats Score at 50.8 and 53.1.

In the 9 individual benchmarks reported for both models, Kimi K3 wins 7; this is a narrower head-to-head signal than the composite indexes.

On price, GPT-5.6 Terra is roughly 1.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5.6 Terra 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-5.6 Terra

  • cost matters — it's about 1.3x cheaper per token
  • you process long inputs — it offers a 1,050,000 token context window

Choose Kimi K3

  • you value its reported benchmark strengths — it wins 7 of 9 exact shared results
  • you want the most recent training data — it shipped Jul 2026
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Core performance indexes
50.8
#15
53.1
#8
49.2
#15
51.8
#8
42.2
#8
43.3
#6
38.2
#10
39.5
#9
Cost, coverage & limits
Benchmark wins
2 of 9
7 of 9
Input price
$2.00 / M
$2.85 / M
Output price
$12.00 / M
$14.25 / M
Context window
1,050,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
GPT-5.6 Terra
Kimi K3
32.4#59
40.9#12
29.9#30
36.3#8
30.2#19
33.9#4
30.6#29
38.1#3
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

45 reported for GPT-5.6 Terra · 31 for Kimi K3

9 shared

GPT-5.6 Terra outperforms in 2 benchmarks (DeepSWE, DeepSWE 1.1), while Kimi K3 is better at 7 benchmarks (AutomationBench, BrowseComp, GPQA, MMMU-Pro, MMMU-Pro (with tools), Terminal-Bench 2.1, Toolathlon).

Kimi K3 significantly outperforms across most benchmarks.

Tue Sep 15 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

GPT-5.6 Terra costs less

For input processing, GPT-5.6 Terra ($2.00/1M tokens) is 1.4x cheaper than Kimi K3 ($2.85/1M tokens).

For output processing, GPT-5.6 Terra ($12.00/1M tokens) is 1.2x cheaper than Kimi K3 ($14.25/1M tokens).

In conclusion, Kimi K3 is more expensive than GPT-5.6 Terra.*

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

Lowest available price from all providers
Tue Sep 15 2026 • llm-stats.com
OpenAI
GPT-5.6 Terra
Input tokens$2.00
Output tokens$12.00
Best providerOpenAI
Moonshot AI
Kimi K3
Input tokens$2.85
Output tokens$14.25
Best providerDeepinfra
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

GPT-5.6 Terra 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-5.6 Terra is limited to 128,000 tokens.

OpenAI
GPT-5.6 Terra
Input1,050,000 tokens
Output128,000 tokens
Moonshot AI
Kimi K3
Input1,048,576 tokens
Output1,048,576 tokens
Tue Sep 15 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both GPT-5.6 Terra and Kimi K3 support multimodal inputs.

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

GPT-5.6 Terra

Text
Images
Audio
Video

Kimi K3

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-5.6 Terra 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-5.6 Terra

Proprietary

Closed source

Kimi K3

Kimi K3 License

Open weights

Release Timeline

When each model was launched

GPT-5.6 Terra was released on 2026-07-09, while Kimi K3 was released on 2026-07-16.

Kimi K3 is 0 month newer than GPT-5.6 Terra.

GPT-5.6 Terra

Jul 9, 2026

2 months ago

Kimi K3

Jul 16, 2026

2 months ago

1w newer

Knowledge Cutoff

When training data ends

GPT-5.6 Terra has a documented knowledge cutoff of 2026-02-16, while Kimi K3's cutoff date is not specified.

We can confirm GPT-5.6 Terra's training data extends to 2026-02-16, but cannot make a direct comparison without Kimi K3's cutoff date.

GPT-5.6 Terra

Feb 2026

Kimi K3

Provider Availability

GPT-5.6 Terra is available from OpenAI. Kimi K3 is available from DeepInfra, Fireworks, Moonshot AI, Novita, Together.

GPT-5.6 Terra

openai logo
OpenAI
Input Price:Input: $2.00/1MOutput Price:Output: $12.00/1M

Kimi K3

deepinfra logo
Deepinfra
Input Price:Input: $2.85/1MOutput Price:Output: $14.25/1M
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-5.6 Terra and Kimi K3 side-by-side, then vote on the output you prefer.

GPT-5.6 Terra
✓ Preferred
Kimi K3
Open in Playground

FAQ

Common questions about GPT-5.6 Terra vs Kimi K3.

Which is better, GPT-5.6 Terra or Kimi K3?

GPT-5.6 Terra and Kimi K3 are closely matched on the LLM Stats Score at 50.8 and 53.1. GPT-5.6 Terra 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-5.6 Terra compare to Kimi K3 in benchmarks?

GPT-5.6 Terra scores Connectors: 100.0%, HealthBench Consensus: 95.1%, Search and Function-Calling: 94.6%, GPQA: 92.9%, Capture-the-Flag Challenges (Internal): 91.8%. Kimi K3 scores MathVision: 97.8%, DeepSearchQA: 95.0%, GPQA: 93.5%, CharXiv-R: 91.3%, BrowseComp: 91.2%.

Is GPT-5.6 Terra cheaper than Kimi K3?

GPT-5.6 Terra is 1.4x cheaper for input tokens. GPT-5.6 Terra costs $2.00/M input and $12.00/M output via openai. Kimi K3 costs $2.85/M input and $14.25/M output via deepinfra.

What are the context window sizes for GPT-5.6 Terra and Kimi K3?

GPT-5.6 Terra 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-5.6 Terra and Kimi K3?

Key differences include LLM Stats Score (50.8 vs 53.1), context window (1.1M vs 1.0M), input pricing ($2.00 vs $2.85/M), licensing (Proprietary vs Kimi K3 License). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5.6 Terra and Kimi K3?

GPT-5.6 Terra is developed by OpenAI and Kimi K3 is developed by Moonshot AI.