Overview
Kimi K2 is Moonshot AI's open-weight base model — a 1-trillion-parameter mixture-of-experts system with 32B active parameters that powers the Kimi assistant. It pairs strong general capability with the long context and tool use that make it a practical backbone for agents, and it's the foundation the reasoning-focused K2 Thinking variant builds on.
As an open-weight model under a modified MIT licence, K2 gives developers direct access to weights and an OpenAI-compatible API at low cost. For workloads that don't need heavy chain-of-thought, the base K2 is faster and cheaper than the Thinking variant while still delivering competitive quality.
What it can do
- 1T-parameter MoE base model
- Long context and solid tool use
- Open weights, low cost
- Foundation for K2 Thinking
Pricing: Low — open weights and cheap API.
Benchmarks
- Params
- 1T total / 32B active
- Licence
- Modified MIT (open weights)
Pros and cons
What works
- Strong general-purpose open model
- Faster/cheaper than the Thinking variant
- Easy to self-host
Trade-offs
- Less deep reasoning than K2 Thinking
- Newer flagship variants exist
The verdict
Kimi K2 is a capable, affordable open-weight generalist and a great default when you don't need K2 Thinking's heavy reasoning. For agents and high-volume work on open weights, it's an easy model to recommend.
Best for: General-purpose open-weight assistant and agent workloads.
Questions
Should I use Kimi K2 or K2 Thinking?
Use base K2 for fast, cheap general tasks; switch to K2 Thinking when a problem needs deep, multi-step reasoning.