---
title: "Letta vs Mem0"
url: https://mdfy.app/ycd01N9A
updated: 2026-05-10T15:36:24.301Z
source: "mdfy.app"
---
# Letta vs Mem0

| | Mem0 | Letta |
|---|---|---|
| Storage | Vector + graph | Hierarchical (core / archival) |
| Authorship | Auto-extract | Auto-extract + manual edit |
| Hosted | Yes | Yes + self-host |
| Format | JSON memories | Block-based |
| OSS | Yes | Yes (formerly MemGPT) |

## Where they differ
Letta inherits MemGPT's "context windows are an OS resource" framing —
core memory (always loaded) vs archival (paged in). Mem0 is flatter:
all memories are vectors, top-K retrieved per turn.

## Where they're similar
Both treat memory as something the system *extracts from* the user's
behavior. Neither makes memory addressable as a URL the user can paste
into a different AI.