Letta vs mem0
A side-by-side comparison of Letta and mem0, two Memory tools, drawn from Ignaite's continuously-verified listings.
Compared from listings verified as of
At a glance
| Attribute | Letta | mem0 |
|---|---|---|
| Category | Memory | Memory |
| Pricing | FREEMIUM | FREEMIUM |
| License | Open core | Open core |
| Deployment | Hybrid | Hybrid |
| Platforms (differs) | API, CLI, macOS, Windows, Linux | API, CLI |
| Model support | BYO key / model | BYO key / model |
| Vendor (differs) | Letta | Mem0 |
| Capabilities (differs) |
|
|
The honest brief
Letta
The productized MemGPT successor — agents edit their own memory blocks (memory-as-OS) to manage a finite context window.
- Self-editing agent memory
- Open source, model-agnostic
- REST APIs + multi-language SDKs
- Reference architecture for memory
- Developer-focused, not no-code
- Memory model has a learning curve
- Younger, evolving framework
mem0
Fastest path to agent memory — extracts distilled facts with a tiny token footprint and the biggest community.
- Quick to adopt, broad framework integrations
- Stores distilled facts, small footprint
- Vector + graph + key-value storage
- Open-source with usable free tier
- Weaker on temporal/state-change queries
- LLM call on every write adds latency
- Test deletion/conflict handling for regulated use
- More library than full memory server
When to pick which
Across the signals we compare, Letta and mem0 differ on platforms:
- Platforms
- API, CLI, macOS, Windows, Linux · API, CLI
Their capability lists differ in recorded depth — compare the full lists above before deciding.