Kastor vs WeWeb 3.0 (2026)
A side-by-side comparison of Kastor and WeWeb 3.0 on pricing, features, and fit, so you can decide which is right for you.
Quick answer
Kastor and WeWeb 3.0 are both strong choices, but they fit different needs. Choose Kastor if you mainly need building multi-step research assistants that delegate subtasks to specialized sub-agents — its edge is completely free and open-source with no licensing fees or usage limits. Choose WeWeb 3.0 if you need building internal business tools without a full engineering team — its edge is combines ai speed with no-code control, reducing risk of broken outputs. Kastor starts at Free; WeWeb 3.0 starts at $49/month for the Starter plan.
Features compared
- Multi-agent orchestration framework for coordinating multiple AI agents simultaneously
- Open-source codebase with full transparency and community-driven development
- Extensible architecture supporting custom LLM backends and tool integrations
- Agent communication and context-sharing protocols for collaborative task execution
- AI-powered app generation from natural language prompts
- Visual no-code drag-and-drop editor as a safety net for AI output
- Native integrations with external databases, REST APIs, and Supabase
- Collaboration tools for teams to build and iterate together
Pros & cons
- Completely free and open-source with no licensing fees or usage limits
- Gives developers full control over agent logic, memory, and integrations
- Active open-source community enables rapid iteration and community-contributed extensions
- Requires developer expertise to set up and configure compared to managed platforms
- Documentation and support may be limited compared to commercial multi-agent frameworks
- Combines AI speed with no-code control, reducing risk of broken outputs
- Strong integration ecosystem supports real production-grade applications
- Suitable for both technical and non-technical users on the same project
- Advanced customization may still require some frontend knowledge for edge cases
- Pricing can become costly for agencies managing multiple client projects
The verdict
Choose Kastor if
you mainly need to building multi-step research assistants that delegate subtasks to specialized sub-agents. Its edge: completely free and open-source with no licensing fees or usage limits.
Choose WeWeb 3.0 if
you mainly need to building internal business tools without a full engineering team. Its edge: combines ai speed with no-code control, reducing risk of broken outputs.
Frequently asked questions
Is Kastor better than WeWeb 3.0?
Neither is universally better. Kastor is stronger for building multi-step research assistants that delegate subtasks to specialized sub-agents, with an edge in completely free and open-source with no licensing fees or usage limits. WeWeb 3.0 is stronger for building internal business tools without a full engineering team, with an edge in combines ai speed with no-code control, reducing risk of broken outputs. Pick based on your main task.
Which is cheaper, Kastor or WeWeb 3.0?
Kastor starts at Free and WeWeb 3.0 starts at $49/month for the Starter plan. Free tier: Kastor — Fully free and open-source; WeWeb 3.0 — Free plan available with limited projects and WeWeb branding.
What is Kastor best for?
Kastor is best for building multi-step research assistants that delegate subtasks to specialized sub-agents, automating complex workflows where multiple ai agents must collaborate and hand off results, prototyping agentic pipelines for startups or research teams without incurring api or platform costs.
What is WeWeb 3.0 best for?
WeWeb 3.0 is best for building internal business tools without a full engineering team, launching customer-facing saas mvps quickly using ai-assisted scaffolding, creating data-driven dashboards connected to external databases.
Do Kastor and WeWeb 3.0 have free plans?
Kastor: Fully free and open-source. WeWeb 3.0: Free plan available with limited projects and WeWeb branding. Check each tool's pricing page for current limits, as plans change.