Curiosity · AI Model

Kimi K2

Kimi K2 is Moonshot AI's 2025 open-weight Mixture-of-Experts model, estimated at around one trillion parameters with 32B active. It is known for ultra-long context (up to 1M tokens in some deployments), strong Chinese and English performance, and a focus on agentic coding — Moonshot markets it as one of the best open models for multi-step tool use.

Model specs

Vendor
Moonshot AI
Family
Kimi
Released
2025-07
Context window
1,000,000 tokens
Modalities
text, code
Input price
$0.6/M tok
Output price
$2.5/M tok
Pricing as of
2026-04-20

Strengths

  • Top-of-class open-weight SWE-bench scores at release
  • Ultra-long context (up to 1M tokens)
  • Aggressive pricing on the Moonshot API and via DeepInfra/Groq
  • Apache-2.0-compatible licence terms

Limitations

  • 1T-parameter MoE is expensive to self-host (needs 8+ H100s)
  • Tooling outside China is still maturing
  • Vision modality not supported in K2

Use cases

  • Long-document summarisation at Chinese-market pricing
  • Agentic coding pipelines on open infrastructure
  • Self-hosted chat for enterprises with data-residency needs
  • Research on MoE open-weight systems

Benchmarks

BenchmarkScoreAs of
SWE-bench Verified~65%2026-04
MMLU-Pro~75%2026-04
LiveCodeBench~55%2026-04

Frequently asked questions

What is Kimi K2?

Kimi K2 is Moonshot AI's flagship open-weight Mixture-of-Experts language model — roughly one trillion total parameters with about 32 billion active per token — optimised for long context and agentic coding.

Is Kimi K2 open-source?

Yes. Moonshot released Kimi K2 weights on HuggingFace under a permissive licence, and inference is offered by third-party providers like DeepInfra and Groq alongside Moonshot's own API.

Sources

  1. Moonshot AI — Kimi K2 on HuggingFace — accessed 2026-04-20
  2. Moonshot AI platform — accessed 2026-04-20