Kimi K2.8 Preview vs o3
Comparing Kimi K2.8 Preview and o3 across benchmarks, pricing, and capabilities.
Moonshot AI · OpenAI · Updated for 2026
Which is better?
Kimi K2.8 Preview and o3 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 o3
- you want predictable pricing at $2.00/M input and $8.00/M output
At a glance
The differences that matter most.
Individual benchmarks
0 reported for Kimi K2.8 Preview · 22 for o3
Kimi K2.8 Preview and o3don'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 o3's 200,000 tokens. Only o3 specifies output context (100,000 tokens).
Input capabilities
Documented input modalities across available providers
Both Kimi K2.8 Preview and o3 support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Kimi K2.8 Preview
o3
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Kimi K2.8 Preview was released on 2026-09-11, while o3 was released on 2025-04-16.
Kimi K2.8 Preview is 17 months newer than o3.
Sep 11, 2026
4 days ago
1.4yr newerApr 16, 2025
1.4 years ago
Knowledge Cutoff
When training data ends
o3 has a documented knowledge cutoff of 2024-05-31, while Kimi K2.8 Preview's cutoff date is not specified.
We can confirm o3's training data extends to 2024-05-31, but cannot make a direct comparison without Kimi K2.8 Preview's cutoff date.
—
May 2024
Provider Availability
Kimi K2.8 Preview is available from Moonshot AI. o3 is available from OpenAI.
Kimi K2.8 Preview
o3
Outputs Comparison
Judge for yourself.
Run your own prompts against Kimi K2.8 Preview and o3 side-by-side, then vote on the output you prefer.
FAQ
Common questions about Kimi K2.8 Preview vs o3.