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Gemini 4 Carbon vs K2 Horizon 375B-A23B

Gemini 4 Carbon leads the LLM Stats Score 59.0 to 38.5.

Google · Institute of Foundation Models · Updated for 2026

Which is better?

Gemini 4 Carbon leads the overall LLM Stats Score 59.0 to 38.5, ranking #2 overall.

In the 1 individual benchmarks reported for both models, Gemini 4 Carbon 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 Gemini 4 Carbon

  • overall performance matters — it scores 59.0 and ranks #2 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 Oct 2026

Choose K2 Horizon 375B-A23B

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

At a glance

The differences that matter most.

Gemini 4 Carbon
Google
K2 Horizon 375B-A23B
Institute of Foundation Models
Core performance indexes
LLM Stats Score
59.0
#2
38.5
#83
Reasoning
54.9
#5
37.3
#87
Coding
48.1
#3
21.2
#114
Agents
46.0
#2
23.9
#74
Cost, coverage & limits
Benchmark wins
1 of 1
0 of 1
Input price
— / M
— / M
Output price
— / M
— / M
Context window
—
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Gemini 4 Carbon
K2 Horizon 375B-A23B
Tool use
35.8#3
22.3#62
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

16 reported for Gemini 4 Carbon · 18 for K2 Horizon 375B-A23B

1 shared

Gemini 4 Carbon outperforms in 1 benchmarks (AutomationBench), while K2 Horizon 375B-A23B is better at 0 benchmarks.

Gemini 4 Carbon significantly outperforms across most benchmarks.

Fri Oct 30 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Input capabilities

Documented input modalities across available providers

Gemini 4 Carbon supports multimodal inputs, whereas K2 Horizon 375B-A23B does not.

Gemini 4 Carbon can handle both text and other forms of data like images, making it suitable for multimodal applications.

Gemini 4 Carbon

Text
Images
Audio
Video

K2 Horizon 375B-A23B

Text
Images
Audio
Video

License

Usage and distribution terms

Gemini 4 Carbon is licensed under a proprietary license, while K2 Horizon 375B-A23B uses Apache 2.0.

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

Gemini 4 Carbon

Proprietary

Closed source

K2 Horizon 375B-A23B

Apache 2.0

Open weights

Release Timeline

When each model was launched

Gemini 4 Carbon was released on 2026-10-28, while K2 Horizon 375B-A23B was released on 2026-09-03.

Gemini 4 Carbon is 2 months newer than K2 Horizon 375B-A23B.

Gemini 4 Carbon

Oct 28, 2026

2 days ago

1mo newer
K2 Horizon 375B-A23B

Sep 3, 2026

1 months ago

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Gemini 4 Carbon and K2 Horizon 375B-A23B side-by-side, then vote on the output you prefer.

Gemini 4 Carbon
✓ Preferred
K2 Horizon 375B-A23B
Open in Playground

FAQ

Common questions about Gemini 4 Carbon vs K2 Horizon 375B-A23B.

Which is better, Gemini 4 Carbon or K2 Horizon 375B-A23B?

Gemini 4 Carbon leads the LLM Stats Score 59.0 to 38.5. Gemini 4 Carbon is made by Google and K2 Horizon 375B-A23B is made by Institute of Foundation Models. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Gemini 4 Carbon compare to K2 Horizon 375B-A23B in benchmarks?

Gemini 4 Carbon scores Gray Swan IPI Benchmark: 100.0%, Vending-Bench 2: 100.0%, Graphwalks BFS >128k: 96.2%, WebDev Arena: 88.4%, SEC-bench Pro: 88.2%. K2 Horizon 375B-A23B scores GPQA: 87.3%, AA-LCR: 76.0%, OmniScience (non-hallucination rate): 74.7%, BrowseComp: 72.8%, Terminal-Bench 2.1: 70.2%.

What are the main differences between Gemini 4 Carbon and K2 Horizon 375B-A23B?

Key differences include LLM Stats Score (59.0 vs 38.5), multimodal support (yes vs no), licensing (Proprietary vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 4 Carbon and K2 Horizon 375B-A23B?

Gemini 4 Carbon is developed by Google and K2 Horizon 375B-A23B is developed by Institute of Foundation Models.

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