What is the difference between OCPUs and vCPUs in OCI?

An OCPU in OCI represents a physical CPU core with hyper-threading, equivalent to two vCPUs in most other cloud providers. So a 4 OCPU shape gives you 8 vCPUs of processing power. This distinction is important when comparing OCI pricing to AWS or Azure — a 4 OCPU OCI instance is comparable to an 8 vCPU instance elsewhere. OCI prices are listed per OCPU, so the effective per-vCPU cost is half the listed OCPU rate.

What are flexible shapes and how do they save costs?

Flexible shapes let you choose the exact number of OCPUs (1 to 64 for most shapes) and memory (1 to 64 GB per OCPU) your workload needs, rather than selecting from fixed sizes. You pay only for the resources you configure. This eliminates the waste of provisioning a fixed shape with 32 GB RAM when your workload only needs 12 GB. Flexible shapes are available for AMD (E4, E5), Intel (Optimized3), and Arm (A1, A2) processors.

Which OCI shape family is best for general-purpose workloads?

For general-purpose workloads, the VM.Standard.E4.Flex (AMD EPYC) and VM.Standard.A1.Flex (Arm Ampere Altra) shapes offer the best price-performance ratio. The A1 Flex shape is particularly cost-effective and is included in the Always Free tier (up to 4 OCPUs and 24 GB RAM). For workloads that require x86 compatibility, the E4 Flex shape provides a good balance of compute, memory, and network bandwidth at competitive pricing.

OCI Compute Shape Finder

ComputeOCI

Find OCI compute shapes by vCPU, memory, and workload type including Ampere ARM.

Shape Requirements

Min OCPUs

Min Memory (GB)

Architecture

Shape Type

Max Price/Hour ($) - Optional

Raw Output

Output will appear here...

About This Tool

OCI offers a wide range of compute shapes spanning AMD, Intel, and Arm-based processors, with both fixed and flexible configurations. Flexible shapes (like VM.Standard.E4.Flex and VM.Standard.A1.Flex) let you choose exact OCPU and memory ratios, while fixed shapes provide predetermined configurations. Choosing the right shape requires understanding OCPU pricing differences between processor families, network bandwidth allocations, local NVMe storage availability, and GPU options. The Compute Shape Finder helps you filter and compare shapes based on your workload requirements, showing pricing, performance characteristics, and availability by region.

When to Use This Tool

•Finding the most cost-effective shape for a Java application server that needs 8 OCPUs and 64 GB RAM across AMD, Intel, and Arm options
•Identifying GPU shapes available in your target region for machine learning training workloads
•Comparing bare metal versus VM shapes for Oracle Database workloads that require high I/O and local NVMe storage
•Evaluating Arm-based A1 shapes versus AMD E4 shapes for containerized microservices where per-OCPU cost matters most

Frequently Asked Questions

What is the difference between OCPUs and vCPUs in OCI?: An OCPU in OCI represents a physical CPU core with hyper-threading, equivalent to two vCPUs in most other cloud providers. So a 4 OCPU shape gives you 8 vCPUs of processing power. This distinction is important when comparing OCI pricing to AWS or Azure — a 4 OCPU OCI instance is comparable to an 8 vCPU instance elsewhere. OCI prices are listed per OCPU, so the effective per-vCPU cost is half the listed OCPU rate.
What are flexible shapes and how do they save costs?: Flexible shapes let you choose the exact number of OCPUs (1 to 64 for most shapes) and memory (1 to 64 GB per OCPU) your workload needs, rather than selecting from fixed sizes. You pay only for the resources you configure. This eliminates the waste of provisioning a fixed shape with 32 GB RAM when your workload only needs 12 GB. Flexible shapes are available for AMD (E4, E5), Intel (Optimized3), and Arm (A1, A2) processors.
Which OCI shape family is best for general-purpose workloads?: For general-purpose workloads, the VM.Standard.E4.Flex (AMD EPYC) and VM.Standard.A1.Flex (Arm Ampere Altra) shapes offer the best price-performance ratio. The A1 Flex shape is particularly cost-effective and is included in the Always Free tier (up to 4 OCPUs and 24 GB RAM). For workloads that require x86 compatibility, the E4 Flex shape provides a good balance of compute, memory, and network bandwidth at competitive pricing.

Related Learning Guides

OCI Compute Shapes & Instances18 min read
OCI Cost Optimization Strategies18 min read

Disclaimer: This tool runs entirely in your browser. No data is sent to our servers. Always verify outputs before using them in production. AWS, Azure, and GCP are trademarks of their respective owners.