MongoDB Atlas

Gotchas

• 512 MB storage cap

  The M0 free cluster is permanently capped at 512 MB of total data storage with no option to expand without upgrading to a paid tier.

• Shared RAM and vCPU

  The free M0 cluster runs on shared RAM and shared vCPU with no dedicated resources, meaning performance is subject to noisy-neighbour effects.

• 100 ops/sec throughput cap

  M0 clusters are limited to a maximum of 100 database operations per second, making them unsuitable for any meaningful production load.

• No backups

  Automated backups and point-in-time restore are not available on the M0 free tier; data loss from accidental deletion or corruption cannot be recovered via Atlas.

• One free cluster per project

  Only one M0 free cluster is permitted per Atlas project; additional clusters require paid tiers.

• No dedicated cluster features

  Features such as replica set configuration, sharding, dedicated search nodes, VPC peering, and private endpoints are unavailable on the free M0 tier.

• Charts refresh limited to 4-hour intervals

  Atlas Charts on M0 clusters auto-refreshes dashboards at most once every 4 hours and restricts email reports to weekly cadence only.

• 32 MB sort memory limit

  In-memory sort operations are capped at 32 MB; queries that exceed this limit without a supporting index will fail.

• No manual chart refresh

  Manual dashboard refresh is disabled on M0; users cannot trigger an on-demand refresh in Atlas Charts.

• App Services free tier: 1M requests/month

  Atlas App Services (Triggers, Functions, Device Sync) share a monthly free allowance of 1 million requests or 500 compute-hours or 10,000 sync-hours plus 10 GB transfer; overages are billed.