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Kimi K2.8 Preview vs Step 3.7 Flash

Comparing Kimi K2.8 Preview and Step 3.7 Flash across benchmarks, pricing, and capabilities.

Moonshot AI · StepFun · Updated for 2026

Which is better?

Kimi K2.8 Preview and Step 3.7 Flash 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 Step 3.7 Flash

  • 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
Step 3.7 Flash
StepFun
Benchmark wins
—
—
Input price
— / M
$0.20 / M
Output price
— / M
$1.15 / M
Context window
1,048,576
262,144

Individual benchmarks

0 reported for Kimi K2.8 Preview · 4 for Step 3.7 Flash

No common benchmarks found

Kimi K2.8 Preview and Step 3.7 Flashdon'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 Step 3.7 Flash's 262,144 tokens. Only Step 3.7 Flash specifies output context (262,144 tokens).

Moonshot AI
Kimi K2.8 Preview
Input1,048,576 tokens
Output- tokens
StepFun
Step 3.7 Flash
Input262,144 tokens
Output262,144 tokens
Sun Sep 20 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Kimi K2.8 Preview and Step 3.7 Flash support multimodal inputs.

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

Kimi K2.8 Preview

Text
Images
Audio
Video

Step 3.7 Flash

Text
Images
Audio
Video

License

Usage and distribution terms

Kimi K2.8 Preview is licensed under a proprietary license, while Step 3.7 Flash uses Apache 2.0.

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

Kimi K2.8 Preview

Proprietary

Closed source

Step 3.7 Flash

Apache 2.0

Open weights

Release Timeline

When each model was launched

Kimi K2.8 Preview was released on 2026-09-11, while Step 3.7 Flash was released on 2026-06-10.

Kimi K2.8 Preview is 3 months newer than Step 3.7 Flash.

Kimi K2.8 Preview

Sep 11, 2026

1 weeks ago

3mo newer
Step 3.7 Flash

Jun 10, 2026

3 months 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. Step 3.7 Flash is available from DeepInfra.

Kimi K2.8 Preview

moonshot logo
Unknown Organization

Step 3.7 Flash

deepinfra logo
Deepinfra
Input Price:Input: $0.20/1MOutput Price:Output: $1.15/1M
* 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 Step 3.7 Flash side-by-side, then vote on the output you prefer.

Kimi K2.8 Preview
✓ Preferred
Step 3.7 Flash
Open in Playground

FAQ

Common questions about Kimi K2.8 Preview vs Step 3.7 Flash.

Which is better, Kimi K2.8 Preview or Step 3.7 Flash?

Kimi K2.8 Preview (Moonshot AI) and Step 3.7 Flash (StepFun) 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 Step 3.7 Flash in benchmarks?

Step 3.7 Flash scores Terminal-Bench 2.1: 59.5%, SWE-Bench Pro: 56.3%, Humanity's Last Exam (with tools, text-only): 47.2%, GDPval: 45.8%.

What are the context window sizes for Kimi K2.8 Preview and Step 3.7 Flash?

Kimi K2.8 Preview supports 1.0M tokens and Step 3.7 Flash supports 262K 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 Step 3.7 Flash?

Key differences include context window (1.0M vs 262K), licensing (Proprietary vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi K2.8 Preview and Step 3.7 Flash?

Kimi K2.8 Preview is developed by Moonshot AI and Step 3.7 Flash is developed by StepFun.

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