Model Comparison

Claude Opus 4.5 vs Kimi K2 InstructWhich is better in 2026?

Claude Opus 4.5 shows notably better performance in the majority of benchmarks. Kimi K2 Instruct is 20.0x cheaper per token.

Verdict: Claude Opus 4.5 vs Kimi K2 Instruct — which is better?

Claude Opus 4.5 (by Anthropic) and Kimi K2 Instruct (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.

Claude Opus 4.5 outperforms in 3 benchmarks (GPQA, Tau2 Retail, Tau2 Telecom), while Kimi K2 Instruct is better at 1 benchmark (LiveBench). Claude Opus 4.5 shows notably better performance in the majority of benchmarks.

On price, Kimi K2 Instruct is roughly 20.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Choose Claude Opus 4.5 if…

  • you want the strongest raw capability — it leads on 3 of 4 shared benchmarks
  • you want the most recent training data — it shipped Nov 2025

Choose Kimi K2 Instruct if…

  • cost matters — it's about 20.0x cheaper per token
  • you need open weights you can self-host or fine-tune

Performance Benchmarks

Comparative analysis across standard metrics

4 benchmarks

Claude Opus 4.5 outperforms in 3 benchmarks (GPQA, Tau2 Retail, Tau2 Telecom), while Kimi K2 Instruct is better at 1 benchmark (LiveBench).

Claude Opus 4.5 shows notably better performance in the majority of benchmarks.

Sun Jul 26 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Kimi K2 Instruct costs less

For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 10.0x more expensive than Kimi K2 Instruct ($0.50/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 50.0x more expensive than Kimi K2 Instruct ($0.50/1M tokens).

In conclusion, Claude Opus 4.5 is more expensive than Kimi K2 Instruct.*

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

Lowest available price from all providers
Sun Jul 26 2026 • llm-stats.com
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
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

Both models have the same input context window of 200,000 tokens. Kimi K2 Instruct can generate longer responses up to 200,000 tokens, while Claude Opus 4.5 is limited to 64,000 tokens.

Anthropic
Claude Opus 4.5
Input200,000 tokens
Output64,000 tokens
Moonshot AI
Kimi K2 Instruct
Input200,000 tokens
Output200,000 tokens
Sun Jul 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Claude Opus 4.5 supports multimodal inputs, whereas Kimi K2 Instruct does not.

Claude Opus 4.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Opus 4.5

Text
Images
Audio
Video

Kimi K2 Instruct

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 4.5 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.

Claude Opus 4.5

Proprietary

Closed source

Kimi K2 Instruct

MIT

Open weights

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while Kimi K2 Instruct was released on 2025-07-11.

Claude Opus 4.5 is 5 months newer than Kimi K2 Instruct.

Claude Opus 4.5

Nov 24, 2025

8 months ago

4mo newer
Kimi K2 Instruct

Jul 11, 2025

1.0 years ago

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a documented knowledge cutoff of 2025-03-31, while Kimi K2 Instruct's cutoff date is not specified.

We can confirm Claude Opus 4.5's training data extends to 2025-03-31, but cannot make a direct comparison without Kimi K2 Instruct's cutoff date.

Claude Opus 4.5

Mar 2025

Kimi K2 Instruct

—

Provider Availability

Claude Opus 4.5 is available from Anthropic. Kimi K2 Instruct is available from Fireworks, Novita.

Claude Opus 4.5

anthropic logo
Anthropic
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M

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

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Supports multimodal inputs
Higher GPQA score (87.0% vs 75.1%)
Higher Tau2 Retail score (88.9% vs 70.6%)
Higher Tau2 Telecom score (98.2% vs 65.8%)
Moonshot AI
Less expensive input tokens
Less expensive output tokens
Has open weights
Higher LiveBench score (76.4% vs 76.0%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Opus 4.5 and Kimi K2 Instruct side-by-side, then vote on the output you prefer.

Claude Opus 4.5
✓ Preferred
Kimi K2 Instruct
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Opus 4.5
Moonshot AI
Kimi K2 Instruct

FAQ

Common questions about Claude Opus 4.5 vs Kimi K2 Instruct.

Which is better, Claude Opus 4.5 or Kimi K2 Instruct?

Claude Opus 4.5 shows notably better performance in the majority of benchmarks. Claude Opus 4.5 is made by Anthropic 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 Claude Opus 4.5 compare to Kimi K2 Instruct in benchmarks?

Claude Opus 4.5 scores Tau2 Telecom: 98.2%, MMMLU: 90.8%, Tau2 Retail: 88.9%, GPQA: 87.0%, SWE-Bench Verified: 80.9%. Kimi K2 Instruct scores MATH-500: 97.4%, GSM8k: 97.3%, CBNSL: 95.6%, HumanEval: 93.3%, MMLU-Redux: 92.7%.

Is Claude Opus 4.5 cheaper than Kimi K2 Instruct?

Kimi K2 Instruct is 10.0x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. Kimi K2 Instruct costs $0.50/M input and $0.50/M output via fireworks.

What are the context window sizes for Claude Opus 4.5 and Kimi K2 Instruct?

Claude Opus 4.5 supports 200K 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 Claude Opus 4.5 and Kimi K2 Instruct?

Key differences include input pricing ($5.00 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 Claude Opus 4.5 and Kimi K2 Instruct?

Claude Opus 4.5 is developed by Anthropic and Kimi K2 Instruct is developed by Moonshot AI.

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