Mem0 vs Zep: which AI memory layer fits your stack
Updated June 28, 2026
Mem0 and Zep are the two most-recommended AI memory layers for production apps, but they make fundamentally different architectural bets. Mem0 extracts discrete facts and retrieves them by semantic search. Zep models facts as a temporal knowledge graph, so it can answer questions about how things changed over time. Which one you need depends almost entirely on whether your data drifts.
Architecture at a glance
Mem0 runs an LLM over your interactions, extracts memories (facts, preferences, events) into a vector store, and retrieves them by semantic similarity. Setup takes about 30 minutes; the free tier is generous; it has connectors for 21+ frameworks including the AWS Agent SDK. Zep stores facts as bi-temporal graph nodes — every fact carries a validity window so stale facts auto-supersede. When a customer's subscription tier changes, Zep records what it was and what it became; Mem0 overwrites.
| Framework | Family | Pricing | Self-host | License |
|---|---|---|---|---|
| Mem0 Mem0 | Managed extract-retrieve | Freemium | Self-host: moderate | Apache-2.0 |
| Zep (Graphiti) Zep / Graphiti | Knowledge graph / GraphRAG | Free + paid | Self-host: heavy | Apache-2.0 |
When each one wins
Choose Mem0 when you need the fastest path to a working memory layer and your facts are stable (user preferences, past interactions, stated goals). Choose Zep when your binding constraint is temporal state — customer accounts, project status, anything where 'what was true last week' matters. Zep's graph model also handles multi-hop questions naturally; Mem0's flat vector store does not.
Benchmark scores
Both frameworks publish LongMemEval and LoCoMo results, though most are self-reported. Take vendor numbers with appropriate skepticism — the gap between self-reported and independently reproduced scores is significant for both. The table below shows available results from our catalog with provenance tagged.
| Framework | Benchmark | Score | Provenance |
|---|---|---|---|
| Mem0 token-efficient algorithm (Apr 2026) | LongMemEval | 94.4% | self-reported |
| Mem0 | LongMemEval | 49.0% | independent |
| Mem0 token-efficient algorithm (Apr 2026) | LoCoMo | 92.5% | self-reported |
| Mem0 token-efficient algorithm (Apr 2026) | BEAM (1M) | 64.1% | self-reported |
| Mem0 token-efficient algorithm (Apr 2026) | BEAM (10M) | 48.6% | self-reported |
| Mem0 | LoCoMo | 66.9% | independent |
| Mem0 | LongMemEval | 62.6% | independent |
| Mem0 | LoCoMo | 54.7% | independent |
| Zep (Graphiti) | LongMemEval | 63.8% | self-reported |
| Zep (Graphiti) | LongMemEval | 90.2% | self-reported |
| Zep (Graphiti) | LongMemEval | 71.2% | independent |
| Zep (Graphiti) | LongMemEval | 58.6% | independent |
| Zep (Graphiti) | LoCoMo | 44.8% | independent |
Pricing and compliance
Both offer free tiers. Mem0's paid tier starts at $19/mo; the graph tier is $249/mo. Zep is open-source (MIT) and self-hostable at no cost; a managed cloud tier is available. For SOC2/HIPAA workloads, Mem0's Scale tier is certified. Verify Zep's current compliance posture directly with their docs before committing for regulated data.
For most teams building a new AI app, Mem0 is the faster start. For teams where customer state drifts — support agents, account managers, anything tracking 'current situation' — Zep's temporal model is worth the additional complexity.