# Mem0 alternative: how to compare hosted agent memory (and move your data with a dry run)

*Disclosure: I'm Mohammed, founder of MemorySync, so read this as a vendor's page. I drafted it with AI assistance and checked every claim against each company's own site and docs as of Oct 25, 2026. Code status: on Oct 25, 2026 I ran the MemorySync Python snippet (memorysync 1.10.1, Python 3.13) against a mocked HTTP transport to confirm the calls it sends, and ran the migration dry run below (memorysync-cli 1.6.1) on a sample Mem0 export. Nothing was sent to a live MemorySync or Mem0 service. The Mem0 call shapes are quoted from MemorySync's migration guide and were not run.*

If you're searching for a "Mem0 alternative", you've usually hit one of three things: a plan limit, a scoping model that doesn't fit how your app identifies users, or a wish to evaluate a second provider before you commit. This page won't tell you Mem0 is bad. It's a mature product with a large community. It gives you the facts you need to compare, side by side, and a low-risk way to test a switch.

## What Mem0 offers today (from Mem0's own pages)

- **Two editions.** Mem0 Platform (managed) and a self-hosted edition. Mem0's docs say both run "the same core extraction and retrieval logic", and the Platform adds hosting and some extra features ([Platform vs self-hosted](https://docs.mem0.ai/platform/platform-vs-oss)).
- **Core API:** `add`, `search`, `get`, `get_all`, `update`, `delete`, `delete_all` and `history`, scoped by `user_id`, `agent_id` and `run_id` (same page).

## What MemorySync offers today (from [memorysync.io](http://memorysync.io) and [docs.memorysync.io](http://docs.memorysync.io))

- **Hosted only.** One API, plus Python and Node SDKs, a CLI and a hosted, closed-source MCP server ([docs](https://docs.memorysync.io?utm_source=hashnode&utm_medium=organic_page&utm_campaign=v5_oct25&utm_content=pseo_mem0-alternative-hosted-agent-memory)).
- **Scope lives in headers.** End-user scope is the `X-End-User-ID` header and project scope is `X-Project-ID`, not filter arguments ([Migrating from Mem0](https://docs.memorysync.io/getting-started/migrate/from-mem0?utm_source=hashnode&utm_medium=organic_page&utm_campaign=v5_oct25&utm_content=pseo_mem0-alternative-hosted-agent-memory)).

## Side by side (as of Oct 25, 2026)

|  | Mem0 | MemorySync |
| --- | --- | --- |
| Deployment | Managed Platform, or self-hosted edition | Managed only |
| User scoping | `user_id` / `agent_id` / `run_id` per call and in `filters` | `X-End-User-ID` header (SDK: `end_user_id=` on the client) |
| Result count arg | `top_k` | `k` |
| Graph memory | On Mem0's Custom plan; removed from the self-hosted edition | Not listed as a plan feature |

Two honest takeaways. If you need to run memory on your own infrastructure, Mem0's self-hosted edition is an option MemorySync does not offer. If your concern is a forgotten `user_id` filter widening a read, MemorySync's design puts the scope in a header the API enforces. Their docs also warn that a *missing* header writes into the wrong scope rather than raising, so map it carefully.

## The call-by-call mapping

From MemorySync's migration guide:

| Mem0 | MemorySync |
| --- | --- |
| `client.add(messages, user_id="alice")` | `client.add("...")` on a client created with `end_user_id="alice"` |
| `client.search(query, filters={"user_id": "alice"}, top_k=5)` | `client.query(query, k=5)` |
| `update(memory_id, text=...)` | `PATCH /memory/{memory_id}` (tags, importance, metadata, source) |
| org/project ids on the client | `X-Project-ID` header |

```python
# MemorySync, from docs.memorysync.io (ran against a mocked transport: sends POST /memory/add and /memory/query with X-End-User-ID: alice)
import os
from memorysync import MemorySyncClient

client = MemorySyncClient(
    api_key=os.environ["MEMORYSYNC_API_KEY"],
    base_url="https://api.memorysync.io",
    end_user_id="alice",
)
client.add("User prefers dark mode")
hits = client.query("user preferences", k=5)
```

## Test a move without risk

1. **Export from Mem0** (dashboard export or export API).
2. **Dry-run the import.** It reports what would be written per user and writes nothing:

   ```bash
   npx memorysync-cli migrate mem0 --file mem0_export.json --dry-run
   ```
3. **Check one user's mapping** before importing everything. Records with no determinable user are refused unless you pass `--source-user <id>`. I checked this on a sample export: the dry run stopped on the record with no `user_id` and wrote nothing, and with `--source-user` it listed that record under the given user.
4. **Run the import** by following the [migration guide](https://docs.memorysync.io/getting-started/migrate/from-mem0?utm_source=hashnode&utm_medium=organic_page&utm_campaign=v5_oct25&utm_content=pseo_mem0-alternative-hosted-agent-memory) once the dry run looks right.
5. **Keep both live** and compare your own real queries, then keep the Mem0 export until you've run a full usage cycle. MemorySync's guide calls that "the cheapest rollback available".

One detail to plan for: per MemorySync's guide, Mem0's `created_at` is kept as `metadata.mem0_created_at`, and MemorySync assigns its own `created_at`. Sort on the metadata field if original order matters.

## Common questions

**Is MemorySync a drop-in replacement for Mem0?** No. The concepts map closely, but the scoping moves from call arguments to a client setting or header, and `top_k` becomes `k`. Expect to touch every call site.

**Can I self-host MemorySync?** Not according to its current site and docs. If self-hosting is a requirement, Mem0's self-hosted edition is the relevant option.

**Do both extract facts rather than store raw text?** Yes, per MemorySync's migration guide. It says the difference is that MemorySync replaces the old value of a one-value fact, such as a city. Its guide says Mem0's April 2026 algorithm adds the new memory alongside the old one.

If you want to see the write/recall loop before you change any code, MemorySync has a browser playground with no signup: [**try it here**](https://memorysync.io/try?utm_source=hashnode&utm_medium=organic_page&utm_campaign=v5_oct25&utm_content=pseo_mem0-alternative-hosted-agent-memory).

## Sources

- Mem0 Platform vs self-hosted: <https://docs.mem0.ai/platform/platform-vs-oss>
- MemorySync, Migrating from Mem0: <https://docs.memorysync.io/getting-started/migrate/from-mem0>
- MemorySync docs home: <https://docs.memorysync.io>
- Mem0, OSS v2 to v3 migration (graph memory removed from OSS): <https://docs.mem0.ai/migration/oss-v2-to-v3>