Model Comparison

Claude Opus 5 vs Kimi K2.5Which is better in 2026?

Claude Opus 5 significantly outperforms across most benchmarks. Kimi K2.5 is 8.3x cheaper per token.

Verdict: Claude Opus 5 vs Kimi K2.5 — which is better?

Claude Opus 5 (by Anthropic) and Kimi K2.5 (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 5 outperforms in 2 benchmarks (BrowseComp, Humanity's Last Exam), while Kimi K2.5 is better at 0 benchmarks. Claude Opus 5 significantly outperforms across most benchmarks.

On price, Kimi K2.5 is roughly 8.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Opus 5 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Claude Opus 5 if…

  • you want the strongest raw capability — it leads on 2 of 2 shared benchmarks
  • you process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Jul 2026

Choose Kimi K2.5 if…

  • cost matters — it's about 8.3x cheaper per token
  • you need open weights you can self-host or fine-tune

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

Claude Opus 5 outperforms in 2 benchmarks (BrowseComp, Humanity's Last Exam), while Kimi K2.5 is better at 0 benchmarks.

Claude Opus 5 significantly outperforms across most benchmarks.

Sun Jul 26 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Kimi K2.5 costs less

For input processing, Claude Opus 5 ($5.00/1M tokens) is 8.3x more expensive than Kimi K2.5 ($0.60/1M tokens).

For output processing, Claude Opus 5 ($25.00/1M tokens) is 8.3x more expensive than Kimi K2.5 ($3.00/1M tokens).

In conclusion, Claude Opus 5 is more expensive than Kimi K2.5.*

* 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 5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
Moonshot AI
Kimi K2.5
Input tokens$0.60
Output tokens$3.00
Best providerFireworks
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Claude Opus 5 accepts 1,000,000 input tokens compared to Kimi K2.5's 262,100 tokens. Kimi K2.5 can generate longer responses up to 262,100 tokens, while Claude Opus 5 is limited to 128,000 tokens.

Anthropic
Claude Opus 5
Input1,000,000 tokens
Output128,000 tokens
Moonshot AI
Kimi K2.5
Input262,100 tokens
Output262,100 tokens
Sun Jul 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Opus 5 and Kimi K2.5 support multimodal inputs.

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

Claude Opus 5

Text
Images
Audio
Video

Kimi K2.5

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 5 is licensed under a proprietary license, while Kimi K2.5 uses MIT.

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

Claude Opus 5

Proprietary

Closed source

Kimi K2.5

MIT

Open weights

Release Timeline

When each model was launched

Claude Opus 5 was released on 2026-07-24, while Kimi K2.5 was released on 2026-01-27.

Claude Opus 5 is 6 months newer than Kimi K2.5.

Claude Opus 5

Jul 24, 2026

2 days ago

5mo newer
Kimi K2.5

Jan 27, 2026

6 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

Provider Availability

Claude Opus 5 is available from Anthropic. Kimi K2.5 is available from Fireworks, Moonshot AI.

Claude Opus 5

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

Kimi K2.5

fireworks logo
Fireworks
Input Price:Input: $0.60/1MOutput Price:Output: $3.00/1M
moonshot logo
Unknown Organization
Input Price:Input: $0.60/1MOutput Price:Output: $3.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Larger context window (1,000,000 tokens)
Higher BrowseComp score (90.8% vs 74.9%)
Higher Humanity's Last Exam score (64.7% vs 50.2%)
Moonshot AI
Less expensive input tokens
Less expensive output tokens
Has open weights

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Opus 5 and Kimi K2.5 side-by-side, then vote on the output you prefer.

Claude Opus 5
✓ Preferred
Kimi K2.5
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Opus 5
Moonshot AI
Kimi K2.5

FAQ

Common questions about Claude Opus 5 vs Kimi K2.5.

Which is better, Claude Opus 5 or Kimi K2.5?

Claude Opus 5 significantly outperforms across most benchmarks. Claude Opus 5 is made by Anthropic and Kimi K2.5 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 5 compare to Kimi K2.5 in benchmarks?

Claude Opus 5 scores BrowseComp: 90.8%, BioMysteryBench: 90.1%, OSWorld 2.0: 70.6%, DeepSWE 1.1: 68.8%, Humanity's Last Exam: 64.7%. Kimi K2.5 scores AIME 2025: 96.1%, HMMT 2025: 95.4%, InfoVQAtest: 92.6%, OCRBench: 92.3%, MathVista-Mini: 90.1%.

Is Claude Opus 5 cheaper than Kimi K2.5?

Kimi K2.5 is 8.3x cheaper for input tokens. Claude Opus 5 costs $5.00/M input and $25.00/M output via anthropic. Kimi K2.5 costs $0.60/M input and $3.00/M output via fireworks.

What are the context window sizes for Claude Opus 5 and Kimi K2.5?

Claude Opus 5 supports 1.0M tokens and Kimi K2.5 supports 262K 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 5 and Kimi K2.5?

Key differences include context window (1.0M vs 262K), input pricing ($5.00 vs $0.60/M), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 5 and Kimi K2.5?

Claude Opus 5 is developed by Anthropic and Kimi K2.5 is developed by Moonshot AI.

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