Quick answer
MongoDB Atlas documents free cluster data storage as 0.5 GB. Stored BSON documents and their indexes count toward the hard cap.
Verified Aug 22, 2026Official source
Current limits
| Constraint | Current value | Scope | Verified source |
|---|---|---|---|
| free cluster data storageStored BSON documents and their indexes count toward the hard cap. | 0.5 GB | Free cluster | MongoDBAug 22, 2026 |
Why does this limit matter?
Index growth can exhaust free storage even when application document bytes appear below 0.5 GB.
This value is scoped to Free cluster; a different plan, runtime, model, endpoint, region, or account can produce a different effective constraint.
What should you check?
- Compare logical data and index sizes with the Atlas storage metric.
- Confirm the exact plan, model, runtime, endpoint, region, and account that serve the failing workload.
- Record the observed value, response headers or configuration, timestamp, and source without logging secrets.
Important caveats
- Free cluster storage cannot auto-expand; upgrade is required for additional capacity.
- Treat the official source and live account configuration as authoritative if they differ from this verified snapshot.
HyperObserve reports the documented platform constraint. Your application, SDK, gateway, provider, region, or account can impose a lower effective limit.
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