Model Comparison

GPT-4o vs Kimi K2 Instruct

Kimi K2 Instruct significantly outperforms across most benchmarks. Kimi K2 Instruct is 8.8x cheaper per token.

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Performance Benchmarks

Comparative analysis across standard metrics

12 benchmarks

GPT-4o outperforms in 2 benchmarks (Humanity's Last Exam, SimpleQA), while Kimi K2 Instruct is better at 10 benchmarks (Aider-Polyglot, AIME 2024, GPQA, IFEval, MMLU, MMLU-Pro, Multi-Challenge, Tau2 Airline, Tau2 Retail, Tau2 Telecom).

Kimi K2 Instruct significantly outperforms across most benchmarks.

Sun May 31 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Kimi K2 Instruct costs less

For input processing, GPT-4o ($2.50/1M tokens) is 5.0x more expensive than Kimi K2 Instruct ($0.50/1M tokens).

For output processing, GPT-4o ($10.00/1M tokens) is 20.0x more expensive than Kimi K2 Instruct ($0.50/1M tokens).

In conclusion, GPT-4o is more expensive than Kimi K2 Instruct.*

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

Lowest available price from all providers
Sun May 31 2026 • llm-stats.com
OpenAI
GPT-4o
Input tokens$2.50
Output tokens$10.00
Best providerAzure
Moonshot AI
Kimi K2 Instruct
Input tokens$0.50
Output tokens$0.50
Best providerFireworks
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Kimi K2 Instruct accepts 200,000 input tokens compared to GPT-4o's 128,000 tokens. Kimi K2 Instruct can generate longer responses up to 200,000 tokens, while GPT-4o is limited to 16,384 tokens.

OpenAI
GPT-4o
Input128,000 tokens
Output16,384 tokens
Moonshot AI
Kimi K2 Instruct
Input200,000 tokens
Output200,000 tokens
Sun May 31 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-4o supports multimodal inputs, whereas Kimi K2 Instruct does not.

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

GPT-4o

Text
Images
Audio
Video

Kimi K2 Instruct

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-4o is licensed under a proprietary license, while Kimi K2 Instruct uses MIT.

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

GPT-4o

Proprietary

Closed source

Kimi K2 Instruct

MIT

Open weights

Release Timeline

When each model was launched

GPT-4o was released on 2024-08-06, while Kimi K2 Instruct was released on 2025-07-11.

Kimi K2 Instruct is 11 months newer than GPT-4o.

GPT-4o

Aug 6, 2024

1.8 years ago

Kimi K2 Instruct

Jul 11, 2025

10 months ago

11mo newer

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

Provider Availability

GPT-4o is available from Azure, OpenAI. Kimi K2 Instruct is available from Fireworks, Novita.

GPT-4o

azure logo
Azure
Input Price:Input: $2.50/1MOutput Price:Output: $10.00/1M
openai logo
OpenAI
Input Price:Input: $2.50/1MOutput Price:Output: $10.00/1M

Kimi K2 Instruct

fireworks logo
Fireworks
Input Price:Input: $0.50/1MOutput Price:Output: $0.50/1M
novita logo
Novita
Input Price:Input: $0.57/1MOutput Price:Output: $2.30/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

OpenAI
Supports multimodal inputs
Higher Humanity's Last Exam score (5.3% vs 4.7%)
Higher SimpleQA score (38.2% vs 31.0%)
Moonshot AI
Larger context window (200,000 tokens)
Less expensive input tokens
Less expensive output tokens
Has open weights
Higher Aider-Polyglot score (60.0% vs 30.7%)
Higher AIME 2024 score (69.6% vs 13.1%)
Higher GPQA score (75.1% vs 70.1%)
Higher IFEval score (89.8% vs 81.0%)
Higher MMLU score (89.5% vs 85.7%)
Higher MMLU-Pro score (81.1% vs 74.7%)
Higher Multi-Challenge score (54.1% vs 40.3%)
Higher Tau2 Airline score (56.5% vs 45.5%)
Higher Tau2 Retail score (70.6% vs 63.4%)
Higher Tau2 Telecom score (65.8% vs 23.5%)

Detailed Comparison

AI Model Comparison Table
Feature
OpenAI
GPT-4o
Moonshot AI
Kimi K2 Instruct

FAQ

Common questions about GPT-4o vs Kimi K2 Instruct.

Which is better, GPT-4o or Kimi K2 Instruct?

Kimi K2 Instruct significantly outperforms across most benchmarks. GPT-4o is made by OpenAI and Kimi K2 Instruct is made by Moonshot AI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-4o compare to Kimi K2 Instruct in benchmarks?

GPT-4o scores AI2D: 94.2%, DocVQA: 92.8%, ChartQA: 85.7%, MMLU: 85.7%, CharXiv-D: 85.3%. Kimi K2 Instruct scores MATH-500: 97.4%, GSM8k: 97.3%, CBNSL: 95.6%, HumanEval: 93.3%, MMLU-Redux: 92.7%.

Is GPT-4o cheaper than Kimi K2 Instruct?

Kimi K2 Instruct is 5.0x cheaper for input tokens. GPT-4o costs $2.50/M input and $10.00/M output via azure. Kimi K2 Instruct costs $0.50/M input and $0.50/M output via fireworks.

What are the context window sizes for GPT-4o and Kimi K2 Instruct?

GPT-4o supports 128K tokens and Kimi K2 Instruct supports 200K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-4o and Kimi K2 Instruct?

Key differences include context window (128K vs 200K), input pricing ($2.50 vs $0.50/M), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-4o and Kimi K2 Instruct?

GPT-4o is developed by OpenAI and Kimi K2 Instruct is developed by Moonshot AI.