Model Comparison

Claude Opus 4.5 vs Kimi K3Which is better in 2026?

Kimi K3 significantly outperforms across most benchmarks. Kimi K3 is 1.7x cheaper per token.

Verdict: Claude Opus 4.5 vs Kimi K3 — which is better?

Claude Opus 4.5 (by Anthropic) and Kimi K3 (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 0 benchmarks, while Kimi K3 is better at 2 benchmarks (GPQA, MCP Atlas). Kimi K3 significantly outperforms across most benchmarks.

On price, Kimi K3 is roughly 1.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Kimi K3 also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Choose Claude Opus 4.5 if…

  • you want predictable pricing at $5.00/M input and $25.00/M output

Choose Kimi K3 if…

  • you want the strongest raw capability — it leads on 2 of 2 shared benchmarks
  • cost matters — it's about 1.7x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Jul 2026

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

Claude Opus 4.5 outperforms in 0 benchmarks, while Kimi K3 is better at 2 benchmarks (GPQA, MCP Atlas).

Kimi K3 significantly outperforms across most benchmarks.

Fri Jul 17 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Kimi K3 costs less

For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 1.7x more expensive than Kimi K3 ($3.00/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 1.7x more expensive than Kimi K3 ($15.00/1M tokens).

In conclusion, Claude Opus 4.5 is more expensive than Kimi K3.*

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

Lowest available price from all providers
Fri Jul 17 2026 • llm-stats.com
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
Moonshot AI
Kimi K3
Input tokens$3.00
Output tokens$15.00
Best providerUnknown Organization
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Kimi K3 accepts 1,048,576 input tokens compared to Claude Opus 4.5's 200,000 tokens. Kimi K3 can generate longer responses up to 1,048,576 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 K3
Input1,048,576 tokens
Output1,048,576 tokens
Fri Jul 17 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Opus 4.5 and Kimi K3 support multimodal inputs.

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

Claude Opus 4.5

Text
Images
Audio
Video

Kimi K3

Text
Images
Audio
Video

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while Kimi K3 was released on 2026-07-16.

Kimi K3 is 8 months newer than Claude Opus 4.5.

Claude Opus 4.5

Nov 24, 2025

7 months ago

Kimi K3

Jul 16, 2026

1 days ago

7mo newer

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a documented knowledge cutoff of 2025-03-31, while Kimi K3'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 K3's cutoff date.

Claude Opus 4.5

Mar 2025

Kimi K3

—

Provider Availability

Claude Opus 4.5 is available from Anthropic. Kimi K3 is available from Moonshot AI.

Claude Opus 4.5

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

Kimi K3

moonshot logo
Unknown Organization
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic

No standout differentiators in the data we have for this pair.

Moonshot AI
Larger context window (1,048,576 tokens)
Less expensive input tokens
Less expensive output tokens
Has open weights
Higher GPQA score (93.5% vs 87.0%)
Higher MCP Atlas score (84.2% vs 62.3%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Opus 4.5 and Kimi K3 side-by-side, then vote on the output you prefer.

Claude Opus 4.5
✓ Preferred
Kimi K3
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Opus 4.5
Moonshot AI
Kimi K3

FAQ

Common questions about Claude Opus 4.5 vs Kimi K3.

Which is better, Claude Opus 4.5 or Kimi K3?

Kimi K3 significantly outperforms across most benchmarks. Claude Opus 4.5 is made by Anthropic and Kimi K3 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 K3 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 K3 scores MathVision: 97.8%, DeepSearchQA: 95.0%, GPQA: 93.5%, CharXiv-R: 91.3%, BrowseComp: 91.2%.

Is Claude Opus 4.5 cheaper than Kimi K3?

Kimi K3 is 1.7x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. Kimi K3 costs $3.00/M input and $15.00/M output via moonshot.

What are the context window sizes for Claude Opus 4.5 and Kimi K3?

Claude Opus 4.5 supports 200K tokens and Kimi K3 supports 1.0M 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 K3?

Key differences include context window (200K vs 1.0M), input pricing ($5.00 vs $3.00/M), licensing (Proprietary vs Unknown). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.5 and Kimi K3?

Claude Opus 4.5 is developed by Anthropic and Kimi K3 is developed by Moonshot AI.

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