In Google Cloud, both Labels and Tags are used for organizing resources, but they serve distinct purposes and have different capabilities. Choosing between them (or using both) depends on your specific needs for resource management, policy enforcement, and cost allocation.
Here’s a comparison to highlight the differences:
| Feature | Labels | Tags |
| Primary Use | Resource organization, filtering, and cost allocation for billing. | Resource management, policy enforcement (IAM, Network Firewall Policies, Organization Policies), hierarchical organization. |
| Structure | Key-value pairs directly attached to a resource. | A separate resource type (TagKey and TagValue) that is bound to a resource. Can have a hierarchical structure (within Tag Keys). |
| Hierarchy | No hierarchy (flat structure). | Can be hierarchical (e.g., OrgID/Environment/Team). |
| Policy Integration | Limited direct integration; useful for filtering in policies or reports. | Tightly integrated with IAM conditions, Network Firewall Policies, and Organization Policies to enforce access or configuration based on tags. |
| Creation | Created directly on the resource. | Tag Keys and Tag Values are created centrally (e.g., at the Organization or Folder level) and then associated with resources via Tag Bindings. |
| Limitations | Up to 64 key-value pairs per resource. Specific key and value formatting rules. | Up to 500 tag bindings per resource. Limits on Tag Keys and Tag Values per organization/folder. |
| Cost Allocation | Yes, widely used for breaking down costs in billing reports. | Yes, can also be used for cost allocation, especially when tied to hierarchical structures. |
Recommendations
1. Use Labels For:
- General-purpose organization (e.g., environment:prod, team:finance, component:frontend).
- Filtering resources in the Cloud Console or using gcloud/APIs.
- Breaking down costs in your billing reports by project, team, application, etc.
2. Use Tags For:
- Applying policies based on resource attributes (e.g., allowing specific network traffic only to VMs with a environment:prod tag).
- Defining IAM policies based on whether a resource has a specific tag.
- Implementing Organization Policies to enforce configurations (e.g., requiring certain security settings for resources with a specific tag).
- Structuring your resource metadata hierarchically.
3. Use Both When:
- You need both the granular, flexible key-value pairing of Labels for detailed cost allocation and filtering, and the policy enforcement and hierarchical capabilities of Tags.
- A common pattern is to use Labels for cost center, application name, etc., and Tags for environment (prod/dev), compliance level, or organizational hierarchy where policies need to be enforced.
In general, if your primary need is policy enforcement or hierarchical organization, Tags are the more powerful and recommended approach. If your primary need is flexible organization, filtering, and detailed cost breakdown, Labels are often sufficient and easier to apply directly. Many organizations benefit from using a combination of both based on their specific governance and operational requirements.
For further details, refer to the official Google Cloud documentation: