Oracle Cloud Infrastructure (OCI) provides a generous Always Free tier designed to help customers explore, build, and sustain lightweight workloads at no cost. While many OCI users are familiar with compute shapes, OCPUs, and metrics, the Always Free program introduces specific usage rules that are often misunderstood—particularly around idle resource reclamation.
This blog explains what Always Free compute is, how the free usage is calculated, and why Oracle may reclaim idle instances.
What Is OCI Always Free Compute?
Always Free is a long-term entitlement within Oracle Cloud Infrastructure that allows customers to run a limited set of resources indefinitely at no charge, provided they stay within defined usage thresholds.
For compute, the most commonly used Always Free option today is:
VM.Standard.A1.Flex (Ampere Arm-based)
This shape provides a monthly free allowance equivalent to:
3,000 OCPU hours
18,000 GB memory hours
In practical terms, this allows customers to run instances totaling up to 4 OCPUs and 24 GB of RAM continuously throughout the month without incurring cost.
How Usage Is Measured (OCPU Hours Explained)
OCI bills (or tracks free usage) based on consumption, not allocation.
An OCPU hour means:
One OCPU used for one hour
Examples:
1 OCPU × 3,000 hours = 3,000 OCPU hours
2 OCPUs × 1,500 hours = 3,000 OCPU hours
4 OCPUs × 24 hours × ~30 days ≈ 2,880 OCPU hours
As long as both OCPU hours and memory hours remain within the free limits, no billing occurs.
Why Oracle Reclaims Always Free Instances
Because Always Free resources are shared and capacity-bound, Oracle enforces governance to prevent long-term reservation of unused infrastructure.
As part of this governance, idle Always Free compute instances may be reclaimed automatically.
What Does “Idle” Mean?
Oracle evaluates Always Free compute instances over a continuous 7-day period. An instance may be classified as idle if all of the following conditions are met during that period:
CPU utilization (95th percentile) is below 20%
Network utilization is below 20%
Memory utilization is below 20% (applies to A1 shapes only)
If these thresholds are consistently unmet, Oracle may stop and reclaim the instance.
Important Clarifications
Reclamation applies only to Always Free resources
Paid compute instances are not subject to this rule
Reclamation is automatic and may occur without prior notice
Boot volumes may remain, but the compute instance itself is removed
The policy is based on sustained inactivity, not brief idle periods
Practical Implications for OCI Users
For users running:
Bastion hosts
Lightweight application servers
Dev/test environments
Monitoring or automation nodes
…it is important to ensure some consistent activity exists. Instances that are powered on but doing “nothing” for extended periods are the most common candidates for reclamation.
Best Practices to Avoid Reclamation
Run periodic workloads or scheduled jobs
Ensure network traffic (even minimal) is present
Monitor CPU, memory, and network metrics
Treat Always Free as active-use infrastructure, not cold standby
Final Thoughts
OCI Always Free is a powerful offering when used as intended—for learning, development, and lightweight production use. Understanding how usage is calculated and how Oracle defines “idle” ensures you can design workloads that remain compliant, predictable, and cost-free.
Used correctly, Always Free compute can be a reliable foundation rather than a surprise outage.
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