---
title: "Mem0 vs Letta: extracted memory comparison"
url: https://mdfy.app/_ybJOqIB
updated: 2026-05-14T18:15:49.480Z
source: "mdfy.app"
---
# Mem0 vs Letta: extracted memory comparison

> Side-by-side after 3 weeks of using both in parallel on the same chat corpus.

## Setup

I forked my Claude Code session log (about 280 conversations, 6 months) and fed it through both Mem0 and Letta. Both got the same input, same time window. I asked each: "Summarise what you know about me as a developer."

## What Mem0 produced

- **Facts.** Direct, dry, accurate. "User is building mdfy.app. User prefers Rust + TypeScript. User has shipped 3 Chrome extensions." Mostly nouns and verbs.
- **Extraction quality.** Strong. It picked up the cross-AI thesis from the corpus correctly, including the specific phrase "structural moat."
- **Misses.** Anything stylistic. It noted "user works in Korean and English" but didn't capture *how* I work in each. The where-and-when-I-write-Korean nuance was invisible.

## What Letta produced

- **Preferences and reflexes.** "User typically reaches for the smallest possible scope when refactoring. User stops feature work when QA finds three issues in a row and shifts to a fix pass."
- **Extraction quality.** Looser but more interesting. The work-shape observations weren't anywhere in any single message; they're inferred from patterns.
- **Misses.** Names of specific tools and products were inconsistent. It flipped between "the editor" and "VS Code" mid-paragraph.

## Where they're the same

Both are **extracted memory**. Both ask the LLM to look at conversation history and produce a profile. The user doesn't author it; the user doesn't directly edit it (though both have "forget that" affordances).

## Where mdfy is doing a different thing

mdfy asks: **what do you want to remember?** The user authors it. The AI reads it. The two questions are complementary, not competing — but they produce different artifacts:

- Mem0/Letta artifact: a generated profile based on what *the AI inferred* you cared about.
- mdfy artifact: a curated hub based on what *you decided* you wanted to keep.

## What I'd love to see

Mem0 + mdfy as siblings: Mem0 produces the inferred profile, you optionally promote any inference to a permanent mdfy doc with one click. The "AI suggested, you author the canonical version" loop.