21st.dev vs Mastra: Agent Frameworks Comparison
Compare 21st.dev and Mastra side by side. Both are tools in the Agent Frameworks category.
Quick Comparison
| Category | Agent Frameworks | Agent Frameworks |
| Pricing | Freemium | Open Source |
| Best For | Developers building and deploying AI agents with UIs | TypeScript developers who want a modern framework for building production AI agents |
| Website | 21st.dev | mastra.ai |
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When to Choose 21st.dev vs Mastra
- Agent deployment
- UI component library for agents
- Full-stack agent development
- TypeScript-native agent development
- Building AI workflows with tool use
- Agent state management
How to Choose a Agent Frameworks Tool
Key criteria to evaluate when comparing Agent Frameworks solutions:
Programming languagePython, TypeScript, or both — must match your team skills and existing codebase.
Architecture patternSingle-agent, multi-agent, or graph-based orchestration depending on task complexity.
Tool ecosystemBuilt-in tools and ease of creating custom tools for your specific needs.
ObservabilityBuilt-in tracing, debugging, and monitoring for understanding agent behavior.
Production readinessError handling, retries, streaming, and deployment options for production use.
About 21st.dev
Infrastructure and UI building blocks for the agentic internet — React component registry pivoting into full agent deployment SDK.
About Mastra
Mastra is a TypeScript-first agent framework for building production AI applications. It provides primitives for agents, workflows, RAG, integrations, and memory with a focus on developer experience and type safety. Mastra is designed for full-stack TypeScript developers who want to build AI features without leaving their existing tech stack.
What is Agent Frameworks?
Developer frameworks and SDKs for building autonomous AI agents with tool use, planning, multi-step reasoning, and orchestration capabilities.
Browse all Agent Frameworks tools →