LeftSize vs Infracost
Infracost shows the cost impact of Terraform, CloudFormation and CDK changes before they are deployed. LeftSize looks at what is already running in your AWS and Azure accounts, including resources created outside code, and opens GitHub issues for waste, retirements and governance gaps. Many teams can use both.
Last checked against Infracost's documentation in October 2026.
| LeftSize | Infracost | |
|---|---|---|
| What it looks at | Live AWS and Azure resources, read-only, whether or not they were created with code | Infrastructure-as-code: cost estimates for Terraform, CloudFormation and CDK |
| When it runs | On a schedule (or on demand) as a GitHub Action | In CI/CD on pull requests |
| Output | GitHub issues per finding group, with remediation steps and @leftsize commands | Cost estimates in pull requests; FinOps policies, Issue Explorer and autofix workflows on the Cloud plan |
| Retirements and end of support | 70 rules for retiring services, VM sizes and end-of-support versions | Not covered on the pricing page |
| Pricing | Free: 77 cost rules, 3 repositories. Team $79/month (10 repositories) or Business $249/month (unlimited), all 188 rules | Free CI/CD plan (1,000 runs/month); Starter $250/month; Cloud $1,000/month; Enterprise on request |
Where Infracost is the better choice
- Shows the cost of a change before it is merged, so waste is prevented instead of found later.
- Works on GitLab and Azure DevOps pipelines as well as GitHub.
- Custom price books and cost guardrails on its paid plans.
What LeftSize adds
- Finds waste that never appears in a pull request: resources created by hand, left behind after deletes, or idle because usage changed.
- Tracks service retirements and end-of-support deadlines on your actual resources.
- Security and governance checks on the same resources.
- Self-serve pricing: Free for cost rules, paid plans from $79/month.
Using them together
Use Infracost to keep expensive changes out of your pull requests, and LeftSize to catch what is already running: idle and orphaned resources, upcoming retirements and governance gaps.