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Kimi K2.8 Preview vs Phi 4 Reasoning Plus

Comparing Kimi K2.8 Preview and Phi 4 Reasoning Plus across benchmarks, pricing, and capabilities.

Moonshot AI · Microsoft · Updated for 2026

Which is better?

Kimi K2.8 Preview and Phi 4 Reasoning Plus trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

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

Choose Kimi K2.8 Preview

  • you want the most recent training data — it shipped Sep 2026

Choose Phi 4 Reasoning Plus

  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Kimi K2.8 Preview
Moonshot AI
Phi 4 Reasoning Plus
Microsoft
Benchmark wins
—
—
Input price
— / M
— / M
Output price
— / M
— / M
Context window
1,048,576
—

Individual benchmarks

0 reported for Kimi K2.8 Preview · 11 for Phi 4 Reasoning Plus

No common benchmarks found

Kimi K2.8 Preview and Phi 4 Reasoning Plusdon'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

Only Kimi K2.8 Preview specifies input context (1,048,576 tokens).

Moonshot AI
Kimi K2.8 Preview
Input1,048,576 tokens
Output- tokens
Microsoft
Phi 4 Reasoning Plus
Input- tokens
Output- tokens
Sun Sep 20 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Kimi K2.8 Preview supports multimodal inputs, whereas Phi 4 Reasoning Plus 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

Phi 4 Reasoning Plus

Text
Images
Audio
Video

License

Usage and distribution terms

Kimi K2.8 Preview is licensed under a proprietary license, while Phi 4 Reasoning Plus uses MIT.

License differences may affect how you can use these models in commercial or open-source projects.

Kimi K2.8 Preview

Proprietary

Closed source

Phi 4 Reasoning Plus

MIT

Open weights

Release Timeline

When each model was launched

Kimi K2.8 Preview was released on 2026-09-11, while Phi 4 Reasoning Plus was released on 2025-04-30.

Kimi K2.8 Preview is 17 months newer than Phi 4 Reasoning Plus.

Kimi K2.8 Preview

Sep 11, 2026

1 weeks ago

1.4yr newer
Phi 4 Reasoning Plus

Apr 30, 2025

1.4 years ago

Knowledge Cutoff

When training data ends

Phi 4 Reasoning Plus has a documented knowledge cutoff of 2025-03-01, while Kimi K2.8 Preview's cutoff date is not specified.

We can confirm Phi 4 Reasoning Plus's training data extends to 2025-03-01, but cannot make a direct comparison without Kimi K2.8 Preview's cutoff date.

Kimi K2.8 Preview

—

Phi 4 Reasoning Plus

Mar 2025

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Kimi K2.8 Preview and Phi 4 Reasoning Plus side-by-side, then vote on the output you prefer.

Kimi K2.8 Preview
✓ Preferred
Phi 4 Reasoning Plus
Open in Playground

FAQ

Common questions about Kimi K2.8 Preview vs Phi 4 Reasoning Plus.

Which is better, Kimi K2.8 Preview or Phi 4 Reasoning Plus?

Kimi K2.8 Preview (Moonshot AI) and Phi 4 Reasoning Plus (Microsoft) 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 Phi 4 Reasoning Plus in benchmarks?

Phi 4 Reasoning Plus scores FlenQA: 97.9%, HumanEval+: 92.3%, IFEval: 84.9%, OmniMath: 81.9%, AIME 2024: 81.3%.

What are the context window sizes for Kimi K2.8 Preview and Phi 4 Reasoning Plus?

Kimi K2.8 Preview supports 1.0M tokens and Phi 4 Reasoning Plus supports an unknown number of 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 Phi 4 Reasoning Plus?

Key differences include multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi K2.8 Preview and Phi 4 Reasoning Plus?

Kimi K2.8 Preview is developed by Moonshot AI and Phi 4 Reasoning Plus is developed by Microsoft.

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