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Kimi K2-Thinking-0905 vs Kimi K3.1 Pro

Kimi K3.1 Pro leads the LLM Stats Score 55.5 to 35.4. Kimi K2-Thinking-0905 is 4.7x cheaper per token.

Moonshot AI · Moonshot AI · Updated for 2026

Which is better?

Kimi K3.1 Pro leads the overall LLM Stats Score 55.5 to 35.4, ranking #5 overall.

In the 3 individual benchmarks reported for both models, Kimi K3.1 Pro wins 3; this is a narrower head-to-head signal than the composite indexes.

On price, Kimi K2-Thinking-0905 is roughly 4.7x 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 Kimi K2-Thinking-0905

  • cost matters — it's about 4.7x cheaper per token
  • you need open weights you can self-host or fine-tune

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 3 of 3 exact shared results
  • 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.

Kimi K2-Thinking-0905
Moonshot AI
Kimi K3.1 Pro
Moonshot AI
Core performance indexes
LLM Stats Score
35.4
#108
55.5
#5
Reasoning
35.6
#101
54.3
#6
Coding
20.5
#119
42.7
#9
Agents
15.3
#113
41.6
#5
Cost, coverage & limits
Benchmark wins
0 of 3
3 of 3
Input price
$0.47 / M
$2.00 / M
Output price
$2.00 / M
$10.00 / M
Context window
262,144
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Kimi K2-Thinking-0905
Kimi K3.1 Pro
Math
37.7#33
38.6#26
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

21 reported for Kimi K2-Thinking-0905 · 30 for Kimi K3.1 Pro

3 shared

Kimi K2-Thinking-0905 outperforms in 0 benchmarks, while Kimi K3.1 Pro is better at 3 benchmarks (BrowseComp, GPQA, Humanity's Last Exam).

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 K2-Thinking-0905 costs less

For input processing, Kimi K2-Thinking-0905 ($0.47/1M tokens) is 4.3x cheaper than Kimi K3.1 Pro ($2.00/1M tokens).

For output processing, Kimi K2-Thinking-0905 ($2.00/1M tokens) is 5.0x cheaper than Kimi K3.1 Pro ($10.00/1M tokens).

In conclusion, Kimi K3.1 Pro is more expensive than Kimi K2-Thinking-0905.*

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

Lowest available price from all providers
Thu Oct 29 2026 • llm-stats.com
Moonshot AI
Kimi K2-Thinking-0905
Input tokens$0.47
Output tokens$2.00
Best providerDeepinfra
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 Kimi K2-Thinking-0905's 262,144 tokens. Kimi K3.1 Pro can generate longer responses up to 1,048,576 tokens, while Kimi K2-Thinking-0905 is limited to 262,144 tokens.

Moonshot AI
Kimi K2-Thinking-0905
Input262,144 tokens
Output262,144 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

Kimi K3.1 Pro supports multimodal inputs, whereas Kimi K2-Thinking-0905 does not.

Kimi K3.1 Pro can handle both text and other forms of data like images, making it suitable for multimodal applications.

Kimi K2-Thinking-0905

Text
Images
Audio
Video

Kimi K3.1 Pro

Text
Images
Audio
Video

Release Timeline

When each model was launched

Kimi K2-Thinking-0905 was released on 2025-09-05, while Kimi K3.1 Pro was released on 2026-10-23.

Kimi K3.1 Pro is 14 months newer than Kimi K2-Thinking-0905.

Kimi K2-Thinking-0905

Sep 5, 2025

1.1 years ago

Kimi K3.1 Pro

Oct 23, 2026

2 days ago

1.1yr 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

Kimi K2-Thinking-0905 is available from DeepInfra, Novita, Fireworks. Kimi K3.1 Pro is available from Moonshot AI.

Kimi K2-Thinking-0905

deepinfra logo
Deepinfra
Input Price:Input: $0.47/1MOutput Price:Output: $2.00/1M
novita logo
Novita
Input Price:Input: $0.48/1MOutput Price:Output: $2.00/1M
fireworks logo
Fireworks
Input Price:Input: $0.60/1MOutput Price:Output: $2.50/1M

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 Kimi K2-Thinking-0905 and Kimi K3.1 Pro side-by-side, then vote on the output you prefer.

Kimi K2-Thinking-0905
✓ Preferred
Kimi K3.1 Pro
Open in Playground

FAQ

Common questions about Kimi K2-Thinking-0905 vs Kimi K3.1 Pro.

Which is better, Kimi K2-Thinking-0905 or Kimi K3.1 Pro?

Kimi K3.1 Pro leads the LLM Stats Score 55.5 to 35.4. Kimi K2-Thinking-0905 is made by Moonshot AI 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 Kimi K2-Thinking-0905 compare to Kimi K3.1 Pro in benchmarks?

Kimi K2-Thinking-0905 scores AIME 2025: 100.0%, HMMT 2025: 97.5%, MMLU-Redux: 94.4%, FRAMES: 87.0%, MMLU-Pro: 84.6%. Kimi K3.1 Pro scores BabyVision: 95.4%, GPQA: 94.2%, BenchCAD (with Python tool): 92.7%, BrowseComp: 92.1%, Chartography: 90.2%.

Is Kimi K2-Thinking-0905 cheaper than Kimi K3.1 Pro?

Kimi K2-Thinking-0905 is 4.3x cheaper for input tokens. Kimi K2-Thinking-0905 costs $0.47/M input and $2.00/M output via deepinfra. Kimi K3.1 Pro costs $2.00/M input and $10.00/M output via moonshot.

What are the context window sizes for Kimi K2-Thinking-0905 and Kimi K3.1 Pro?

Kimi K2-Thinking-0905 supports 262K 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 Kimi K2-Thinking-0905 and Kimi K3.1 Pro?

Key differences include LLM Stats Score (35.4 vs 55.5), context window (262K vs 1.0M), input pricing ($0.47 vs $2.00/M), multimodal support (no vs yes), licensing (MIT vs Unknown). See the full comparison above for benchmark-by-benchmark results.

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