Both sit in the memory layer with similar commercial terms, so the practical split is language: Zep targets Python and LangMem targets Python.
Temporal knowledge graph memory — facts with validity windows, not just embeddings.
Memory primitives that plug straight into LangGraph checkpoints.
| Zep | LangMem | |
|---|---|---|
| Licence | Open source | Open source |
| Pricing | freemium | open source |
| Self-hostable | Yes | Yes |
| Languages | Python, TypeScript | Python |
| Install | — | pip install langmem |
| Keys required | ZEP_API_KEY | None |
| Benchmark | Zep | LangMem |
|---|---|---|
| LoCoMo | 79.09% independent 58.44% independent | 78.05% independent |
Both sit in the memory layer with similar commercial terms, so the practical split is language: Zep targets Python and LangMem targets Python. Zep: Temporal knowledge graph memory — facts with validity windows, not just embeddings. LangMem: Memory primitives that plug straight into LangGraph checkpoints.
Zep can run on your own infrastructure. LangMem can run on your own infrastructure.
Zep is open source (freemium). LangMem is open source (open source).
Every page here answers to Accept: text/markdown and returns the same content at roughly a tenth the tokens. No separate site, no toggle — same URL.
curl -s -H "Accept: text/markdown" https://newagent.build/compare/zep-vs-langmem