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Kimi K2.8 Preview vs o1

Comparing Kimi K2.8 Preview and o1 across benchmarks, pricing, and capabilities.

Moonshot AI · OpenAI · Updated for 2026

Which is better?

Kimi K2.8 Preview and o1 trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

Kimi K2.8 Preview 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 K2.8 Preview

  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose o1

  • you want predictable pricing at $15.00/M input and $60.00/M output

At a glance

The differences that matter most.

Benchmark wins
Input price
— / M
$15.00 / M
Output price
— / M
$60.00 / M
Context window
1,048,576
200,000

Individual benchmarks

0 reported for Kimi K2.8 Preview · 19 for o1

No common benchmarks found

Kimi K2.8 Preview and o1don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Kimi K2.8 Preview accepts 1,048,576 input tokens compared to o1's 200,000 tokens. Only o1 specifies output context (100,000 tokens).

Moonshot AI
Kimi K2.8 Preview
Input1,048,576 tokens
Output- tokens
OpenAI
o1
Input200,000 tokens
Output100,000 tokens
Tue Sep 15 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Kimi K2.8 Preview supports multimodal inputs, whereas o1 does not.

Kimi K2.8 Preview can handle both text and other forms of data like images, making it suitable for multimodal applications.

Kimi K2.8 Preview

Text
Images
Audio
Video

o1

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Kimi K2.8 Preview

Proprietary

Closed source

o1

Proprietary

Closed source

Release Timeline

When each model was launched

Kimi K2.8 Preview was released on 2026-09-11, while o1 was released on 2024-12-17.

Kimi K2.8 Preview is 21 months newer than o1.

Kimi K2.8 Preview

Sep 11, 2026

4 days ago

1.7yr newer
o1

Dec 17, 2024

1.7 years 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

Kimi K2.8 Preview is available from Moonshot AI. o1 is available from Azure, OpenAI.

Kimi K2.8 Preview

moonshot logo
Unknown Organization

o1

azure logo
Azure
Input Price:Input: $15.00/1MOutput Price:Output: $60.00/1M
openai logo
OpenAI
Input Price:Input: $15.00/1MOutput Price:Output: $60.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Kimi K2.8 Preview and o1 side-by-side, then vote on the output you prefer.

Kimi K2.8 Preview
✓ Preferred
o1
Open in Playground

FAQ

Common questions about Kimi K2.8 Preview vs o1.

Which is better, Kimi K2.8 Preview or o1?

Kimi K2.8 Preview (Moonshot AI) and o1 (OpenAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Kimi K2.8 Preview compare to o1 in benchmarks?

o1 scores GSM8k: 97.1%, MATH: 96.4%, GPQA Physics: 92.8%, MMLU: 91.8%, MGSM: 89.3%.

What are the context window sizes for Kimi K2.8 Preview and o1?

Kimi K2.8 Preview supports 1.0M tokens and o1 supports 200K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Kimi K2.8 Preview and o1?

Key differences include context window (1.0M vs 200K), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi K2.8 Preview and o1?

Kimi K2.8 Preview is developed by Moonshot AI and o1 is developed by OpenAI.