Mem0 is a free, open source ai development platforms project written in Python and released under Apache-2.0. It has 65,505 GitHub stars, 7,683 forks and 742 open issues, and was last pushed 8 hours ago. On this registry it ranks #11 of 61 tracked projects in AI Development Platforms, with 5 head-to-head comparisons available. It gained 316 stars over the last 6 tracked days.

Mem0 — Persistent memory layer for AI agents and apps

What is Mem0?

What it is

Mem0 is an open-source memory layer for AI agents and applications, designed to store, retrieve, and manage persistent context across interactions. It lives in the Python-based AI development ecosystem and provides infrastructure that enables agents and apps to remember user preferences, conversation history, and state over time—moving beyond ephemeral chat sessions toward truly adaptive systems.

The project solves the problem of context loss in AI interactions by offering a structured, queryable memory store that persists across sessions and agents. Unlike basic vector databases or ad-hoc context injection, Mem0 provides temporal reasoning, entity linking, and multi-signal retrieval out of the box, ensuring relevant past information surfaces accurately without requiring developers to build retrieval logic from scratch.

Key capabilities

  • Single-pass ADD-only memory extraction using one LLM call, no UPDATE/DELETE operations
  • Agent-generated facts stored with equal weight as user-provided facts
  • Entity linking across memories for boosted retrieval via entity matching
  • Multi-signal retrieval combining semantic, BM25 keyword, and entity signals
  • Temporal reasoning to rank memories by query intent (past, present, future)
  • Multi-level memory: user, session, and agent state with adaptive personalization
  • Cross-platform SDKs for Python and JavaScript/Node.js

Who uses it and how

  • AI assistant developers use it to maintain consistent, personalized conversations across sessions
  • Customer support teams integrate it to recall user history and past tickets for tailored responses
  • Healthcare apps store and retrieve patient preferences and interaction history for continuity of care
  • Productivity and gaming apps adapt workflows or environments based on long-term user behavior
  • Teams self-host the server to run Mem0 on their own infrastructure with dashboard and auth

Getting started

Install via pip install mem0ai for the library, or run docker compose up for self-hosted deployment. A managed cloud option is available at app.mem0.ai. CLI agents can sign up in under five seconds with mem0 init --agent and begin adding/searching memories immediately.

When to use it — and when not to

Use Mem0 when persistent, personalized memory is required for agents or apps and you need built-in retrieval logic (temporal, entity-aware, multi-signal). Avoid it if you require full control over memory schema or storage backend, or if your use case doesn’t need long-term memory across sessions. Self-hosting requires managing PostgreSQL, vector store (e.g., Qdrant), and optional SMTP for notifications—no database is embedded. The open-source SDK delivers directionally similar gains to the managed platform but not identical benchmark numbers due to proprietary optimizations in the cloud version.

project readme (upstream, from github) — read inline

mem0ai%2Fmem0 | Trendshift

Learn more · Join Discord · Demo

Mem0 Discord Mem0 PyPI - Downloads GitHub commit activity Package version Npm package Y Combinator S24

📄 Benchmarking Mem0's token-efficient memory algorithm →

New Memory Algorithm (April 2026)

Benchmark Old New Tokens Latency p50
LoCoMo 71.4 92.5 7.0K 0.88s
LongMemEval 67.8 94.4 6.8K 1.09s
BEAM (1M) 64.1 6.7K 1.00s
BEAM (10M) 48.6 6.9K 1.05s

All benchmarks run on the same production-representative model stack. Single-pass retrieval (one call, no agentic loops) at a top_200 retrieval budget. Scores reflect Mem0's managed platform, which includes proprietary optimizations not available in the open-source SDK; open-source users should expect directionally similar gains but not identical numbers.

What changed:

  • Single-pass ADD-only extraction -- one LLM call, no UPDATE/DELETE. Memories accumulate; nothing is overwritten.
  • Agent-generated facts are first-class -- when an agent confirms an action, that information is now stored with equal weight.
  • Entity linking -- entities are extracted, embedded, and linked across memories for retrieval boosting.
  • Multi-signal retrieval -- semantic, BM25 keyword, and entity matching scored in parallel and fused.
  • Temporal Reasoning -- time-aware retrieval that ranks the right dated instance for queries about current state, past events, and upcoming plans.

See the migration guide for upgrade instructions. The evaluation framework is open-sourced so anyone can reproduce the numbers.

Research Highlights

  • 92.5 on LoCoMo -- +21 points over the previous algorithm
  • 94.4 on LongMemEval -- +27 points, with 98.2 on assistant memory recall
  • 64.1 on BEAM (1M) -- production-scale memory evaluation at 1M tokens
  • Read the full paper

Introduction

Mem0 ("mem-zero") enhances AI assistants and agents with an intelligent memory layer, enabling personalized AI interactions. It remembers user preferences, adapts to individual needs, and continuously learns over time—ideal for customer support chatbots, AI assistants, and autonomous systems.

Key Features & Use Cases

Core Capabilities:

  • Multi-Level Memory: Seamlessly retains User, Session, and Agent state with adaptive personalization
  • Developer-Friendly: Intuitive API, cross-platform SDKs, and a fully managed service option

Applications:

  • AI Assistants: Consistent, context-rich conversations
  • Customer Support: Recall past tickets and user history for tailored help
  • Healthcare: Track patient preferences and history for personalized care
  • Productivity & Gaming: Adaptive workflows and environments based on user behavior

🚀 Quickstart Guide

Sign up as an agent

AI agents can mint a working Mem0 API key in under five seconds — no email, no dashboard, no OTP. Four commands end-to-end:

# 1. Install
npm install -g @mem0/cli      # or: pip install mem0-cli

# 2. Sign up as an agent (replace `claude-code` with your name)
mem0 init --agent --agent-caller claude-code

# 3. Add a memory
mem0 add "I am using mem0"

# 4. Search
mem0 search "am I using mem0"

The human owner can claim the account later with mem0 init --email — same key, memories preserved. Full guide: Sign up as an agent.

Library Self-Hosted Server Cloud Platform
Best for Testing, prototyping Teams running on their own infrastructure Zero-ops production use
Setup pip install mem0ai docker compose up Sign up at app.mem0.ai
Dashboard -- Yes Yes
Auth & API Keys -- Yes Yes
Advanced Features -- Teasers All included

Just testing? Use the library. Building for a team? Self-hosted. Want zero ops? Cloud.

Library (pip / npm)

pip install mem0ai

For enhanced hybrid search with BM25 keyword matching and entity extraction, install with NLP support:

pip install mem0ai[nlp]
python -m spacy download en_core_web_sm

Install sdk via npm:

npm install mem0ai

Self-Hosted Server

Note: Self-hosted auth is on by default. Upgrading from a pre-auth build? Set ADMIN_API_KEY, register an admin through the wizard, or AUTH_DISABLED=true for local dev only. See upgrade notes.

# Recommended: one command — start the stack, create an admin, issue the first API key.
cd server && make bootstrap

# Manual: start the stack and finish setup via the browser wizard.
cd server && docker compose up -d    # http://localhost:3000

See the self-hosted docs for configuration.

Cloud Platform

  1. Sign up on Mem0 Platform
  2. Embed the memory layer via SDK or API keys
  3. Using hosted Qdrant vectors? See the Platform migration guide to import them into Mem0 Platform.

CLI

Manage memories from your terminal:

npm install -g @mem0/cli   # or: pip install mem0-cli

mem0 init
mem0 add "Prefers dark mode and vim keybindings" --user-id alice
mem0 search "What does Alice prefer?" --user-id alice

See the CLI documentation for the full command reference.

Agent Skills

Teach your AI coding assistant (Claude Code, Codex, Cursor, Windsurf, OpenCode, OpenClaw, and any tool that supports the skills standard) how to build with Mem0. Two categories:

Reference skills — always on (SDK knowledge loaded into the assistant's context):

npx skills add https://github.com/mem0ai/mem0 --skill mem0
npx skills add https://github.com/mem0ai/mem0 --skill mem0-cli
npx skills add https://github.com/mem0ai/mem0 --skill mem0-vercel-ai-sdk

Pipeline skills — run on demand (execute an end-to-end workflow in an existing repo):

npx skills add https://github.com/mem0ai/mem0 --skill mem0-integrate
npx skills add https://github.com/mem0ai/mem0 --skill mem0-test-integration
npx skills add https://github.com/mem0ai/mem0 --skill mem0-oss-to-platform

Use /mem0-integrate to wire Mem0 into an existing repo via a test-first pipeline, then /mem0-test-integration to verify. Use /mem0-oss-to-platform to migrate an existing project from Mem0 OSS to the hosted Platform SDK. See the skills catalog or Vibecoding with Mem0 for the full picture.

Basic Usage

Mem0 requires an LLM to function, with gpt-5-mini from OpenAI as the default. However, it supports a variety of LLMs; for details, refer to our Supported LLMs documentation.

Mem0 uses text-embedding-3-small from OpenAI as the default embedding model. For best results with hybrid search (semantic + keyword + entity boosting), we recommend using at least [Qwen 600M](https://huggin

readme truncated — read the full docs on github

Frequently asked questions

Is Mem0 free to use?

Mem0 is open source under the Apache-2.0 licence. There is no licence fee and no seat count — you can self-host it or, where the project offers one, pay a vendor for a managed version instead.

What does Mem0 do?

Persistent memory layer for AI agents and apps

What is Mem0 written in?

Mem0 is primarily written in Python. Its source is publicly available at https://github.com/mem0ai/mem0, and it has 65,505 GitHub stars.