Agno vs 
Letta
Agno vs Letta compared for 2026 — features, license, ease of use, performance and which one to choose. Fast, lightweight multi-modal agents vs Stateful agents with long-term memory.
Updated regularly · curated by OpenSourceAI.tech
Agno vs Letta at a glance
| Spec | Agno | Letta |
|---|---|---|
| Category | AI agent framework | AI agent framework |
| Type | Agent framework | Agent runtime (memory) |
| License | MPL-2.0 | Apache-2.0 |
| Runs locally | Cloud-optional | Self-hosted |
| Primary language | Python | Python |
| Ease of use | Intermediate | Advanced |
| Best for | fast agents with memory and tools | agents that remember across sessions |
| GitHub stars | 41.5k | 24k |
How Agno and Letta score
| Criterion | Agno | Letta |
|---|---|---|
| Popularity | 4.0 | 3.5 |
| Maintenance | 5.0 | 5.0 |
| Ease of use | 3.5 | 2.5 |
| Privacy | 3.5 | 4.5 |
| License freedom | 3.5 | 5.0 |
Scores are computed automatically from public signals — GitHub stars (popularity), recent commit activity (maintenance), license type (freedom), local-first design (privacy) and onboarding complexity (ease of use). Indicative, not a verdict.
What each one is
Agno
Agno (formerly Phidata) is a lightweight, high-performance framework for building multi-modal agents with memory, knowledge and tools, plus a monitoring UI.
- Very fast agent instantiation
- Built-in memory, knowledge and tools
- Multi-modal and model-agnostic
Letta
Letta (formerly MemGPT) is a framework and server for building stateful agents with long-term memory that persists across sessions, with a visual agent editor.
- Persistent long-term agent memory
- Server with REST API and visual editor
- Model-agnostic and self-hostable
Key differences
Agno is agent framework, while Letta is agent runtime (memory). Their licenses differ (MPL-2.0 vs Apache-2.0), which matters if you ship a commercial product. Agno leans more intermediate-friendly, whereas Letta is more suited to advanced users. They also differ in how they run (Cloud-optional vs Self-hosted). In short, Agno fits fast agents with memory and tools, and Letta fits agents that remember across sessions.
Which should you choose?
Choose Agno for fast agents with memory and tools. Choose Letta for agents that remember across sessions.
There is rarely one winner — many setups use both. The right pick depends on your hardware, your team's skills, and whether you value simplicity or control.
Frequently asked questions
Is Agno or Letta easier to use?
Agno is generally the easier of the two to get started with, while Letta rewards more setup with more control.
Are Agno and Letta free?
Agno is free and open source (MPL-2.0), and Letta is free and open source (Apache-2.0). Neither charges for the core software.
Can I run Agno and Letta locally?
Agno: cloud-optional · Letta: self-hosted. Both can be used without sending your data to a third-party cloud where their setup allows.
Agno vs Letta — which should I pick in 2026?
Choose Agno for fast agents with memory and tools. Choose Letta for agents that remember across sessions.
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