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GPT-5.6 Sol vs Kimi K3.1 Pro

GPT-5.6 Sol and Kimi K3.1 Pro are closely matched at 52.7 and 55.5 on the LLM Stats Score. Kimi K3.1 Pro is 2.8x cheaper per token.

OpenAI · Moonshot AI · Updated for 2026

Which is better?

GPT-5.6 Sol and Kimi K3.1 Pro are closely matched on the overall LLM Stats Score at 52.7 and 55.5.

In the 12 individual benchmarks reported for both models, Kimi K3.1 Pro wins 9; this is a narrower head-to-head signal than the composite indexes.

On price, Kimi K3.1 Pro is roughly 2.8x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5.6 Sol also accepts a larger context window (1,050,000 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 GPT-5.6 Sol

  • you process long inputs — it offers a 1,050,000 token context window

Choose Kimi K3.1 Pro

  • you value its reported benchmark strengths — it wins 9 of 12 exact shared results
  • cost matters — it's about 2.8x cheaper per token
  • you want the most recent training data — it shipped Oct 2026

At a glance

The differences that matter most.

Core performance indexes
52.7
#13
55.5
#5
51.5
#9
54.3
#6
42.4
#11
42.7
#9
39.0
#10
41.6
#5
Cost, coverage & limits
Benchmark wins
3 of 12
9 of 12
Input price
$5.00 / M
$2.00 / M
Output price
$30.00 / M
$10.00 / M
Context window
1,050,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

5 shared
Index
GPT-5.6 Sol
Kimi K3.1 Pro
34.0#53
38.6#26
33.8#21
40.5#4
29.3#22
30.4#14
33.9#19
40.8#2
28.3#3
24.5#5
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

45 reported for GPT-5.6 Sol · 30 for Kimi K3.1 Pro

12 shared

GPT-5.6 Sol outperforms in 3 benchmarks (Agents' Last Exam, ExploitGym, GPQA), while Kimi K3.1 Pro is better at 9 benchmarks (BenchCAD, BenchCAD (with Python tool), BrowseComp, DeepSWE, ExploitBench, GDP.pdf, MMMU-Pro, MMMU-Pro (with tools), Terminal-Bench 4.0).

Kimi K3.1 Pro shows notably better performance in the majority of 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, GPT-5.6 Sol ($5.00/1M tokens) is 2.5x more expensive than Kimi K3.1 Pro ($2.00/1M tokens).

For output processing, GPT-5.6 Sol ($30.00/1M tokens) is 3.0x more expensive than Kimi K3.1 Pro ($10.00/1M tokens).

In conclusion, GPT-5.6 Sol 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
OpenAI
GPT-5.6 Sol
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
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

GPT-5.6 Sol accepts 1,050,000 input tokens compared to Kimi K3.1 Pro's 1,048,576 tokens. Kimi K3.1 Pro can generate longer responses up to 1,048,576 tokens, while GPT-5.6 Sol is limited to 128,000 tokens.

OpenAI
GPT-5.6 Sol
Input1,050,000 tokens
Output128,000 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 GPT-5.6 Sol and Kimi K3.1 Pro support multimodal inputs.

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

GPT-5.6 Sol

Text
Images
Audio
Video

Kimi K3.1 Pro

Text
Images
Audio
Video

Release Timeline

When each model was launched

GPT-5.6 Sol was released on 2026-07-09, while Kimi K3.1 Pro was released on 2026-10-23.

Kimi K3.1 Pro is 4 months newer than GPT-5.6 Sol.

GPT-5.6 Sol

Jul 9, 2026

3 months ago

Kimi K3.1 Pro

Oct 23, 2026

6 days ago

3mo newer

Knowledge Cutoff

When training data ends

GPT-5.6 Sol has a documented knowledge cutoff of 2026-02-16, while Kimi K3.1 Pro's cutoff date is not specified.

We can confirm GPT-5.6 Sol's training data extends to 2026-02-16, but cannot make a direct comparison without Kimi K3.1 Pro's cutoff date.

GPT-5.6 Sol

Feb 2026

Kimi K3.1 Pro

—

Provider Availability

GPT-5.6 Sol is available from OpenAI. Kimi K3.1 Pro is available from Moonshot AI.

GPT-5.6 Sol

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M

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 GPT-5.6 Sol and Kimi K3.1 Pro side-by-side, then vote on the output you prefer.

GPT-5.6 Sol
✓ Preferred
Kimi K3.1 Pro
Open in Playground

FAQ

Common questions about GPT-5.6 Sol vs Kimi K3.1 Pro.

Which is better, GPT-5.6 Sol or Kimi K3.1 Pro?

GPT-5.6 Sol and Kimi K3.1 Pro are closely matched on the LLM Stats Score at 52.7 and 55.5. GPT-5.6 Sol is made by OpenAI 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 GPT-5.6 Sol compare to Kimi K3.1 Pro in benchmarks?

GPT-5.6 Sol scores Connectors: 100.0%, Capture-the-Flag Challenges (Internal): 96.7%, HealthBench Consensus: 95.5%, GPQA: 94.6%, MRCR v2 (8-needle): 91.5%. Kimi K3.1 Pro scores BabyVision: 95.4%, GPQA: 94.2%, BenchCAD (with Python tool): 92.7%, BrowseComp: 92.1%, Chartography: 90.2%.

Is GPT-5.6 Sol cheaper than Kimi K3.1 Pro?

Kimi K3.1 Pro is 2.5x cheaper for input tokens. GPT-5.6 Sol costs $5.00/M input and $30.00/M output via openai. Kimi K3.1 Pro costs $2.00/M input and $10.00/M output via moonshot.

What are the context window sizes for GPT-5.6 Sol and Kimi K3.1 Pro?

GPT-5.6 Sol supports 1.1M 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 GPT-5.6 Sol and Kimi K3.1 Pro?

Key differences include LLM Stats Score (52.7 vs 55.5), context window (1.1M vs 1.0M), input pricing ($5.00 vs $2.00/M), licensing (Proprietary vs Unknown). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5.6 Sol and Kimi K3.1 Pro?

GPT-5.6 Sol is developed by OpenAI and Kimi K3.1 Pro is developed by Moonshot AI.