MoonshotAI: Kimi K2 Thinking

Text input Text output
Author's Description

Kimi K2 Thinking is Moonshot AI’s most advanced open reasoning model to date, extending the K2 series into agentic, long-horizon reasoning. Built on the trillion-parameter Mixture-of-Experts (MoE) architecture introduced in Kimi K2, it activates 32 billion parameters per forward pass and supports 256 k-token context windows. The model is optimized for persistent step-by-step thought, dynamic tool invocation, and complex reasoning workflows that span hundreds of turns. It interleaves step-by-step reasoning with tool use, enabling autonomous research, coding, and writing that can persist for hundreds of sequential actions without drift. It sets new open-source benchmarks on HLE, BrowseComp, SWE-Multilingual, and LiveCodeBench, while maintaining stable multi-agent behavior through 200–300 tool calls. Built on a large-scale MoE architecture with MuonClip optimization, it combines strong reasoning depth with high inference efficiency for demanding agentic and analytical tasks.

Key Specifications
Cost
$$$$$
Context
262K
Parameters
1T (Rumoured)
Released
Nov 06, 2025
Speed
Ability
Reliability
Supported Parameters

This model supports the following parameters:

Top P Reasoning Tool Choice Temperature Stop Structured Outputs Response Format Max Tokens Tools Presence Penalty Frequency Penalty Include Reasoning
Features

This model supports the following features:

Structured Outputs Response Format Reasoning Tools
Performance Summary

MoonshotAI's Kimi K2 Thinking model, an advanced open reasoning model, demonstrates exceptional reliability with a 100% success rate across all benchmarks, indicating consistent and stable operation. However, it tends to have longer response times, ranking in the 1st percentile for speed, and is positioned at premium pricing levels, ranking in the 13th percentile for cost. Despite its slower speed and higher cost, Kimi K2 Thinking excels in several critical areas. It achieves near-perfect accuracy in Coding (97.6%, 99th percentile) and Mathematics (96.8%, 99th percentile), placing it among the top performers in these demanding categories. Its Instruction Following capability is also outstanding at 88.5% accuracy (96th percentile), making it the most accurate model at its price point for this task. The model also achieves perfect accuracy in Ethics (100%), showcasing strong moral reasoning. While its General Knowledge (99.5%, 72nd percentile) and Email Classification (99.0%, 70th percentile) are solid, its Hallucinations accuracy (90.0%, 37th percentile) suggests some room for improvement in acknowledging uncertainty. Its Reasoning performance is respectable at 83.7% (73rd percentile). The model's strength lies in its ability to handle complex, multi-step tasks, leveraging its agentic architecture for autonomous research, coding, and writing over hundreds of turns.

Model Pricing

Current Pricing

Feature Price (per 1M tokens)
Prompt $0.4
Completion $1.75

Price History

Available Endpoints
Provider Endpoint Name Context Length Pricing (Input) Pricing (Output)
Moonshot AI
Moonshot AI | moonshotai/kimi-k2-thinking-20251106 262K $0.4 / 1M tokens $1.75 / 1M tokens
Moonshot AI
Moonshot AI | moonshotai/kimi-k2-thinking-20251106 262K $1.15 / 1M tokens $8 / 1M tokens
Parasail
Parasail | moonshotai/kimi-k2-thinking-20251106 128K $0.4 / 1M tokens $1.75 / 1M tokens
Moonshot AI
Moonshot AI | moonshotai/kimi-k2-thinking-20251106 262K $0.6 / 1M tokens $2.5 / 1M tokens
Novita
Novita | moonshotai/kimi-k2-thinking-20251106 262K $0.48 / 1M tokens $2 / 1M tokens
Parasail
Parasail | moonshotai/kimi-k2-thinking-20251106 262K $0.5 / 1M tokens $2.5 / 1M tokens
Chutes
Chutes | moonshotai/kimi-k2-thinking-20251106 262K $0.4 / 1M tokens $1.75 / 1M tokens
GMICloud
GMICloud | moonshotai/kimi-k2-thinking-20251106 262K $0.8 / 1M tokens $1.2 / 1M tokens
Fireworks
Fireworks | moonshotai/kimi-k2-thinking-20251106 262K $0.4 / 1M tokens $1.75 / 1M tokens
Together
Together | moonshotai/kimi-k2-thinking-20251106 262K $1.2 / 1M tokens $4 / 1M tokens
DeepInfra
DeepInfra | moonshotai/kimi-k2-thinking-20251106 262K $0.4 / 1M tokens $1.75 / 1M tokens
AtlasCloud
AtlasCloud | moonshotai/kimi-k2-thinking-20251106 262K $0.6 / 1M tokens $2.5 / 1M tokens
Google
Google | moonshotai/kimi-k2-thinking-20251106 262K $0.6 / 1M tokens $2.5 / 1M tokens
SiliconFlow
SiliconFlow | moonshotai/kimi-k2-thinking-20251106 262K $0.55 / 1M tokens $2.5 / 1M tokens
BaseTen
BaseTen | moonshotai/kimi-k2-thinking-20251106 262K $0.6 / 1M tokens $2.5 / 1M tokens
Nebius
Nebius | moonshotai/kimi-k2-thinking-20251106 262K $0.6 / 1M tokens $2.5 / 1M tokens
DeepInfra
DeepInfra | moonshotai/kimi-k2-thinking-20251106 131K $0.47 / 1M tokens $2 / 1M tokens
Benchmark Results
Benchmark Category Reasoning Strategy Free Executions Accuracy Cost Duration
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