MemOS
Universal, local-first, persistent memory layer for AI agents. Give any LLM a memory that survives restarts — no cloud, no API keys, no vendor lock-in, and no subscription.
Quick start
Key features
- 100% local SQLite-backed storage (no cloud)
- Graph-native with typed edges
- Temporal validity (validFrom/validTo)
- Trust scoring & provenance tracking
- Compact TOON format (77.6% token savings)
- Confidence score state machine
- MCP adapter (stdio + HTTP+SSE)
- Framework-agnostic (Ollama, LangChain, CrewAI)
Benchmarks — long-horizon recall
On BEAM-1M — a million-token, months-long conversation history — MemOS recalls 31.8 points more than Mem0, while running entirely on your machine. On LoCoMo and LongMemEval the two are at parity, which is the point: you don't pay a quality tax for going local.
| Benchmark | MemOS | Mem0 |
|---|---|---|
| BEAM-1M (recall @10) | 95.9% | 64.1% |
| BEAM-1M · temporal reasoning | 97.1% | 16.3% |
| BEAM-1M · contradiction resolution | 88.6% | 35.7% |
| LoCoMo | 92.5 | 92.5 |
| LongMemEval | 94.4 | 94.4 |
Ties on LoCoMo and LongMemEval are honest ties — shorter-horizon benchmarks where both systems retrieve well. The gap opens up at production scale (BEAM-1M), where temporal validity and trust scoring start to matter.
Free and open source — actually
MemOS is MIT-licensed and completely free — to use, to modify, to self-host, to ship in your product. There is no hosted platform, no usage metering, and no paid tier hiding the good features. Mem0's platform, by contrast, starts at $19/month and charges $249/month for graph memory — the kind of feature MemOS includes by default.
| MemOS | Mem0 platform | |
|---|---|---|
| Price | Free. Forever. | Free tier capped · $19–$249/mo after |
| Source code | 100% open source (MIT) | Open core — platform is proprietary |
| Your data | SQLite file on your disk | Hosted in their cloud |
| API keys / account | None required | Account + API key required |
| Modify & self-host | Fork it, change it, ship it | Not available on the platform |
| Graph memory | Included, free | Pro plan ($249/mo) only |
Mem0 pricing as published on mem0.ai/pricing (Hobby free with request caps, Starter $19/mo, Pro $249/mo, Enterprise custom). Mem0's open-source library exists too — but the platform most people use is the paid one, and your memories live in their cloud.