Hy4 preview vs Kimi: Features, Pricing & Which Is Better (2026)
A side-by-side comparison of Hy4 preview and Kimi — features, pricing, and ideal use cases — to help you decide which AI tool fits your workflow.
Hy4 preview
Tencent
Tencent's open-weight Hy4 preview, a 770B-parameter Mixture-of-Experts model with 49B active parameters and a 1M-token context window.
Key features
- 770B Mixture-of-Experts Architecture: Holds 770 billion total parameters while activating only 49 billion per token, so capacity scales without proportional inference cost.
- 1M-Token Context Window: Accepts inputs exceeding one million tokens, allowing whole codebases, long document sets or extended agent traces in a single prompt.
- Apache 2.0 Open Weights: Released under a permissive licence that allows commercial use, modification and redistribution with no separate agreement.
- Productivity Task Focus: Tuned for real-world coding, office work and scientific research rather than narrow benchmark optimisation.
- Multi-Product Availability: Accessible globally through Tencent's WorkBuddy, CodeBuddy, Yuanbao and ima applications in addition to the raw weights.
- API Access via TokenHub and OpenRouter: Can be called through Tencent Cloud TokenHub or OpenRouter for teams that prefer hosted inference over self-hosting.
Best for
- Whole-Repository Code Work: Load an entire codebase into the million-token context to reason about refactors and cross-file dependencies at once.
- Long-Horizon Agent Tasks: Drive multi-step agent workflows where the full history of tool calls and intermediate results must stay in context.
- Self-Hosted Deployment: Run a frontier-scale open-weight model on private infrastructure where data cannot leave the organisation.
- Scientific Literature Analysis: Ingest large collections of papers or experimental logs and synthesise findings without chunking the input.
- Office Document Processing: Summarise, draft and restructure long reports, contracts and spreadsheets in enterprise workflows.
- Commercial Fine-Tuning: Adapt the weights for a proprietary product under the Apache 2.0 licence without negotiating a model licence.
Kimi
Kimi
An open-source trillion-parameter Mixture-of-Experts (MoE) model for coding assistance, intelligent agents, and automated workflows.
Key features
- Trillion-Parameter MoE Architecture: Uses a Mixture-of-Experts design to provide very high model capacity while routing requests to specialized expert subnetworks to improve efficiency and performance on diverse tasks.
- Coding Assistance Optimized: Trained and positioned to assist with code generation, completion, debugging hints, and reasoning about programming tasks to accelerate developer workflows.
- Agent Enablement: Built to serve as the core reasoning and action-planning component for intelligent agents, enabling multi-step task execution, tool use, and orchestration of external APIs.
- Workflow Automation Support: Designed to be integrated into automated pipelines for triggering, generating, and transforming content or code as part of end-to-end automation scenarios.
- Open-Source Availability: Distributed with open-source code and model artifacts (as stated), enabling researchers and engineers to inspect, fine-tune, and deploy the model in custom environments.
- Integration-Ready Tooling: Intended to provide integration points (SDKs, inference code, or examples) so developers can embed K2 into IDEs, CI/CD systems, or agent frameworks (as promoted on the official site).
- Scalable Deployment: MoE design and model packaging aim to support scalable deployments across research and production clusters, balancing inference cost and capacity via expert routing.
- Trillion-parameter MoE model architecture (Kimi K2) with sparse expert activation for efficiency
- Very large context windows (8k / 32k / 128k / 262k variants depending on model)
- Hosted conversational product with file uploads, document export and web search
- Usage-based token pricing for API model inference
- Subscription tiers with higher context, priority queues, multi-file uploads and team features
- Enterprise offerings with dedicated support, admin tools, compliance and on‑prem options
- Trillion-parameter scale model (K2)
- Mixture-of-Experts (MoE) architecture for specialized expert routing
- Designed for advanced code generation and coding assistance
- Intended to power intelligent agents and agent orchestration
- Targeted at automating workflows and developer automation tasks
- Open-source release enabling self-hosting and research use
Best for
- IDE Code Assistant: Embedding Kimi K2 into a developer IDE to provide context-aware code completion, refactor suggestions, and inline debugging guidance for multiple programming languages.
- Autonomous Agent Backbone: Using K2 as the reasoning core of an intelligent agent that composes API calls, plans multi-step tasks, and interacts with external tools to complete workflows.
- Automated Workflow Generation: Generating and orchestrating automation scripts or pipeline steps (e.g., CI jobs, deployment scripts) based on high-level user prompts or repository context.
- Custom Model Fine-Tuning: Researchers and engineering teams fine-tuning the open-source K2 weights on domain-specific codebases to improve performance for proprietary languages, frameworks, or internal APIs.
- Codebase Analysis and Migration: Leveraging K2 to analyze large legacy codebases, produce modernization suggestions, and generate scaffolded code to accelerate migration to newer frameworks.
- Tooling Integration for DevOps: Integrating K2 into DevOps tooling to create automated change suggestions, generate infrastructure-as-code snippets, or help diagnose build failures from logs.
- Long-form writing, multi-document research and multi-session memory
- Code generation, debugging, and VS Code integration
- Agentic workflows and automated pipelines
- Customer support assistants and knowledge-base Q&A across large contexts
- Academic research and prototyping via low-cost/approved API quotas
- Code generation, completion, and advanced coding assistance within developer tools
- Building and running intelligent agents that coordinate tasks and trigger workflows
- Automating multi-step developer or business workflows (orchestration)
- Research and experimentation with large-scale MoE architectures
- Self-hosted deployments for privacy-sensitive or on-premises use cases