Model Comparison

GPT-5.4 vs Kimi K2-Instruct-0905Which is better in 2026?

GPT-5.4 significantly outperforms across most benchmarks.

Verdict: GPT-5.4 vs Kimi K2-Instruct-0905 — which is better?

GPT-5.4 (by OpenAI) and Kimi K2-Instruct-0905 (by Moonshot AI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

GPT-5.4 outperforms in 3 benchmarks (GPQA, Humanity's Last Exam, Tau2 Telecom), while Kimi K2-Instruct-0905 is better at 0 benchmarks. GPT-5.4 significantly outperforms across most benchmarks.

Choose GPT-5.4 if…

  • you want the strongest raw capability — it leads on 3 of 3 shared benchmarks
  • you want the most recent training data — it shipped Mar 2026

Choose Kimi K2-Instruct-0905 if…

  • you need open weights you can self-host or fine-tune
Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

3 benchmarks

GPT-5.4 outperforms in 3 benchmarks (GPQA, Humanity's Last Exam, Tau2 Telecom), while Kimi K2-Instruct-0905 is better at 0 benchmarks.

GPT-5.4 significantly outperforms across most benchmarks.

Sat Jun 13 2026 • llm-stats.com

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only GPT-5.4 specifies input context (1,000,000 tokens). Only GPT-5.4 specifies output context (128,000 tokens).

OpenAI
GPT-5.4
Input1,000,000 tokens
Output128,000 tokens
Moonshot AI
Kimi K2-Instruct-0905
Input- tokens
Output- tokens
Sat Jun 13 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-5.4 supports multimodal inputs, whereas Kimi K2-Instruct-0905 does not.

GPT-5.4 can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-5.4

Text
Images
Audio
Video

Kimi K2-Instruct-0905

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-5.4 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-5.4

Proprietary

Closed source

Kimi K2-Instruct-0905

MIT

Open weights

Release Timeline

When each model was launched

GPT-5.4 was released on 2026-03-05, while Kimi K2-Instruct-0905 was released on 2025-09-05.

GPT-5.4 is 6 months newer than Kimi K2-Instruct-0905.

GPT-5.4

Mar 5, 2026

3 months ago

6mo newer
Kimi K2-Instruct-0905

Sep 5, 2025

9 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?Start an Issue discussion→

Key Takeaways

OpenAI
Larger context window (1,000,000 tokens)
Supports multimodal inputs
Higher GPQA score (92.8% vs 75.1%)
Higher Humanity's Last Exam score (39.8% vs 4.7%)
Higher Tau2 Telecom score (98.9% vs 65.8%)
Moonshot AI
Has open weights

Detailed Comparison

AI Model Comparison Table
Feature
OpenAI
GPT-5.4
Moonshot AI
Kimi K2-Instruct-0905

FAQ

Common questions about GPT-5.4 vs Kimi K2-Instruct-0905.

Which is better, GPT-5.4 or Kimi K2-Instruct-0905?

GPT-5.4 significantly outperforms across most benchmarks. GPT-5.4 is made by OpenAI and Kimi K2-Instruct-0905 is made by Moonshot AI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-5.4 compare to Kimi K2-Instruct-0905 in benchmarks?

GPT-5.4 scores Tau2 Telecom: 98.9%, ARC-AGI: 93.7%, Graphwalks BFS <128k: 93.0%, GPQA: 92.8%, Graphwalks parents <128k: 89.8%. 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-5.4 and Kimi K2-Instruct-0905?

GPT-5.4 supports 1.0M 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-5.4 and Kimi K2-Instruct-0905?

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

Who makes GPT-5.4 and Kimi K2-Instruct-0905?

GPT-5.4 is developed by OpenAI and Kimi K2-Instruct-0905 is developed by Moonshot AI.

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