How do ECR lifecycle policy rules interact when there are multiple rules?

Rules are evaluated in priority order (lowest number first). Each image is evaluated against rules sequentially, and the first matching rule determines its fate. Higher priority rules take precedence, so put your most important retention rules at the lowest priority numbers.

Can lifecycle policies accidentally delete images that are in use?

Lifecycle policies evaluate based on image age and count, not active usage. Images currently deployed by ECS or EKS could be deleted if they match a cleanup rule. Use tag-based rules carefully and ensure actively deployed image tags are excluded from cleanup patterns.

Does this tool apply the policy to my ECR repository?

No. The tool generates the lifecycle policy JSON in your browser. You apply it to your ECR repository via the AWS Console, CLI, or infrastructure-as-code tools like CloudFormation or Terraform.

AWS ECR Lifecycle Policy Builder

ComputeAWS

Build ECR image lifecycle policies for age, count, and tag patterns.

Last verified: May 2026

ECR Lifecycle Policy Configuration

Rule 1 (Priority 1)

Description

Tag Status

Count Type

Days

Generated ECR Lifecycle Policy

Output will appear here...

About This Tool

The ECR Lifecycle Policy Builder helps you create lifecycle policies for Amazon Elastic Container Registry repositories. ECR lifecycle policies automatically clean up old or unused container images based on rules you define, such as image age, count, or tag status. This tool provides a visual interface for building these rules with proper priority ordering and tag pattern matching, then generates the JSON policy you can apply to your repository.

Real-World Scenario

Your platform team's ECR storage bill hit $180/month across 30 repositories. You audit with the builder and create a standard policy: priority 1 = 'keep last 10 production-tagged images', priority 2 = 'expire untagged images >7 days old', priority 3 = 'expire dev-tagged images >30 days old'. Apply across all 30 repos via Terraform. Storage drops from 1.8 TB to 240 GB within a week. New monthly bill: $24. Annual savings: ~$1,900.

When to Use This Tool

•Build lifecycle rules to automatically delete untagged images older than a specified number of days to reclaim storage.
•Create policies that keep only the most recent N images per tag prefix, ensuring you retain recent releases while cleaning up old builds.
•Configure rules that prioritize tagged production images over development or CI images for cleanup ordering.
•Generate lifecycle policies for repositories across multiple environments with consistent image retention standards.

Pro Tips

TIP

ECR storage costs $0.10/GB/month — sounds tiny until you have a 500-image repository accumulated over 2 years × 200 MB/image = 100 GB = $10/month for that ONE repo. Multiply across dozens of repos and you're paying $200-500/month for images nobody uses. Lifecycle policies pay for themselves in weeks.

TIP

Rule priority matters and is non-obvious. Higher numerical priority = evaluated FIRST (opposite of what you might expect). When deletion rules conflict (e.g., 'keep last 10' and 'delete >30 days old'), the higher-priority rule wins. Plan your priority order carefully — ECR will silently apply only the first matching rule per image.

TIP

ECR lifecycle policies don't delete images that are CURRENTLY referenced by a running ECS service or Lambda function. This is mostly a safety feature, but it also means a long-running production deployment can keep an old image alive indefinitely. Always verify that 'kept' images aren't actually orphaned production references.

How It Works Under the Hood

The builder constructs an ECR lifecycle policy JSON document with rules ordered by priority, each containing a description, a selection (matches by tag status, tag prefix, image age, or image count), and an action (currently only 'expire'). It validates that priorities are unique and outputs the JSON ready for `aws ecr put-lifecycle-policy` or aws_ecr_lifecycle_policy in Terraform.

Frequently Asked Questions

How do ECR lifecycle policy rules interact when there are multiple rules?: Rules are evaluated in priority order (lowest number first). Each image is evaluated against rules sequentially, and the first matching rule determines its fate. Higher priority rules take precedence, so put your most important retention rules at the lowest priority numbers.
Can lifecycle policies accidentally delete images that are in use?: Lifecycle policies evaluate based on image age and count, not active usage. Images currently deployed by ECS or EKS could be deleted if they match a cleanup rule. Use tag-based rules carefully and ensure actively deployed image tags are excluded from cleanup patterns.
Does this tool apply the policy to my ECR repository?: No. The tool generates the lifecycle policy JSON in your browser. You apply it to your ECR repository via the AWS Console, CLI, or infrastructure-as-code tools like CloudFormation or Terraform.

Featured In

Was this tool helpful?

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.