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Claude 3.5 Sonnet vs Kimi K3.1 Pro

Kimi K3.1 Pro leads the LLM Stats Score 55.5 to 18.5. Kimi K3.1 Pro is 1.5x cheaper per token.

Anthropic · Moonshot AI · Updated for 2026

Which is better?

Kimi K3.1 Pro leads the overall LLM Stats Score 55.5 to 18.5, ranking #5 overall.

In the 1 individual benchmarks reported for both models, Kimi K3.1 Pro wins 1; this is a narrower head-to-head signal than the composite indexes.

On price, Kimi K3.1 Pro is roughly 1.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

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

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude 3.5 Sonnet

  • you want predictable pricing at $3.00/M input and $15.00/M output

Choose Kimi K3.1 Pro

  • overall performance matters — it scores 55.5 and ranks #5 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results
  • cost matters — it's about 1.5x 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 Oct 2026

At a glance

The differences that matter most.

Claude 3.5 Sonnet
Anthropic
Kimi K3.1 Pro
Moonshot AI
Core performance indexes
LLM Stats Score
18.5
#243
55.5
#5
Reasoning
19.5
#224
54.3
#6
Coding
11.0
#188
42.7
#9
Cost, coverage & limits
Benchmark wins
0 of 1
1 of 1
Input price
$3.00 / M
$2.00 / M
Output price
$15.00 / M
$10.00 / M
Context window
200,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
Claude 3.5 Sonnet
Kimi K3.1 Pro
Math
23.2#144
38.6#26
Vision
14.3#117
40.5#4
Tool use
8.0#167
30.4#14
Multimodal
17.4#96
40.8#2
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

19 reported for Claude 3.5 Sonnet · 30 for Kimi K3.1 Pro

1 shared

Claude 3.5 Sonnet outperforms in 0 benchmarks, while Kimi K3.1 Pro is better at 1 benchmark (GPQA).

Kimi K3.1 Pro significantly outperforms across most benchmarks.

Thu Oct 29 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Kimi K3.1 Pro costs less

For input processing, Claude 3.5 Sonnet ($3.00/1M tokens) is 1.5x more expensive than Kimi K3.1 Pro ($2.00/1M tokens).

For output processing, Claude 3.5 Sonnet ($15.00/1M tokens) is 1.5x more expensive than Kimi K3.1 Pro ($10.00/1M tokens).

In conclusion, Claude 3.5 Sonnet is more expensive than Kimi K3.1 Pro.*

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

Lowest available price from all providers
Thu Oct 29 2026 • llm-stats.com
Anthropic
Claude 3.5 Sonnet
Input tokens$3.00
Output tokens$15.00
Best providerAnthropic
Moonshot AI
Kimi K3.1 Pro
Input tokens$2.00
Output tokens$10.00
Best providerUnknown Organization
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Kimi K3.1 Pro accepts 1,048,576 input tokens compared to Claude 3.5 Sonnet's 200,000 tokens. Kimi K3.1 Pro can generate longer responses up to 1,048,576 tokens, while Claude 3.5 Sonnet is limited to 200,000 tokens.

Anthropic
Claude 3.5 Sonnet
Input200,000 tokens
Output200,000 tokens
Moonshot AI
Kimi K3.1 Pro
Input1,048,576 tokens
Output1,048,576 tokens
Thu Oct 29 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude 3.5 Sonnet and Kimi K3.1 Pro support multimodal inputs.

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

Claude 3.5 Sonnet

Text
Images
Audio
Video

Kimi K3.1 Pro

Text
Images
Audio
Video

Release Timeline

When each model was launched

Claude 3.5 Sonnet was released on 2024-10-22, while Kimi K3.1 Pro was released on 2026-10-23.

Kimi K3.1 Pro is 24 months newer than Claude 3.5 Sonnet.

Claude 3.5 Sonnet

Oct 22, 2024

2.0 years ago

Kimi K3.1 Pro

Oct 23, 2026

2 days ago

2.0yr 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

Claude 3.5 Sonnet is available from Anthropic, Bedrock, Google. Kimi K3.1 Pro is available from Moonshot AI.

Claude 3.5 Sonnet

anthropic logo
Anthropic
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
bedrock logo
AWS Bedrock
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
google logo
Google
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

Kimi K3.1 Pro

moonshot logo
Unknown Organization
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude 3.5 Sonnet and Kimi K3.1 Pro side-by-side, then vote on the output you prefer.

Claude 3.5 Sonnet
✓ Preferred
Kimi K3.1 Pro
Open in Playground

FAQ

Common questions about Claude 3.5 Sonnet vs Kimi K3.1 Pro.

Which is better, Claude 3.5 Sonnet or Kimi K3.1 Pro?

Kimi K3.1 Pro leads the LLM Stats Score 55.5 to 18.5. Claude 3.5 Sonnet is made by Anthropic and Kimi K3.1 Pro is made by Moonshot AI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude 3.5 Sonnet compare to Kimi K3.1 Pro in benchmarks?

Claude 3.5 Sonnet scores GSM8k: 96.4%, DocVQA: 95.2%, AI2D: 94.7%, HumanEval: 93.7%, BIG-Bench Hard: 93.1%. Kimi K3.1 Pro scores BabyVision: 95.4%, GPQA: 94.2%, BenchCAD (with Python tool): 92.7%, BrowseComp: 92.1%, Chartography: 90.2%.

Is Claude 3.5 Sonnet cheaper than Kimi K3.1 Pro?

Kimi K3.1 Pro is 1.5x cheaper for input tokens. Claude 3.5 Sonnet costs $3.00/M input and $15.00/M output via anthropic. Kimi K3.1 Pro costs $2.00/M input and $10.00/M output via moonshot.

What are the context window sizes for Claude 3.5 Sonnet and Kimi K3.1 Pro?

Claude 3.5 Sonnet supports 200K tokens and Kimi K3.1 Pro 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 3.5 Sonnet and Kimi K3.1 Pro?

Key differences include LLM Stats Score (18.5 vs 55.5), context window (200K vs 1.0M), input pricing ($3.00 vs $2.00/M), licensing (Proprietary vs Unknown). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude 3.5 Sonnet and Kimi K3.1 Pro?

Claude 3.5 Sonnet is developed by Anthropic and Kimi K3.1 Pro is developed by Moonshot AI.

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