LeftSize is a cloud optimization tool built for developer workflows. Its positioning is similar to “Dependabot for cloud optimization”: instead of forcing teams into a separate FinOps dashboard, it automatically turns cost, governance, security, and deprecation-risk findings from AWS and Azure into GitHub Issues, with explanations, remediation paths, or command scripts attached.
Based on the information on the page, LeftSize covers 107 policies, including idle VMs, unattached disks, missing savings plans, missing Azure Hybrid Benefit, missing tags, unencrypted disks, public storage, open security groups, AKS configuration issues, and deprecated VM SKUs/runtimes. It lets users select repositories through a GitHub App, then runs scans in GitHub Actions using the user’s own AWS/Azure credentials. It supports OIDC, short-lived tokens, and GitHub secrets. Its security model emphasizes that credentials never leave the runner; LeftSize only receives lightweight finding metadata such as resource IDs, costs, and configuration details.
The page clearly mentions a free tier and no credit card requirement, but it does not disclose paid plans, usage limits, or enterprise pricing. Ease of use is a strong point: install the GitHub App, add a workflow file, and wait for Issues to be generated. The sample YAML clearly shows Azure OIDC login and how to call leftsize-action, making it suitable for teams already using GitHub Actions to try quickly.
The main advantage is that findings go directly into GitHub Issues, reducing the need for developers to switch between emails, spreadsheets, and FinOps dashboards. It also avoids requiring teams to hand over long-lived cloud account credentials, which lowers security concerns. The downsides are also clear: the current copy only mentions AWS and Azure, with no sign of GCP; it depends on GitHub workflows, making it less friendly to GitLab, self-hosted CI, or non-GitHub organizations; and its documentation, SLA, permission boundaries, and pricing details are still not fully presented.
LeftSize is a good fit for SaaS startups without a dedicated FinOps team, platform engineering teams, and organizations that want to shift cloud governance responsibilities left into the development process. Its accessibility from China cannot be determined from the page. If a team’s access to GitHub Actions or the AWS/Azure control planes is affected by network conditions, the actual experience may depend on the company’s network environment. Alternatives include AWS Trusted Advisor, Azure Advisor, CloudHealth, Cloudability, Vantage, Infracost, or self-built scanning based on Steampipe/CloudQuery.
⚠ This review is compiled from public sources and does not constitute a purchase recommendation. Verify all facts on the vendor's official site. Verify on leftsize.com official site.
leftsize.com is an United States Dev Tools provider. TG4G tracks its product information, an overall rating of 8.0/10, and a China-accessibility score of Workable. Click "Visit Official Site" to reach leftsize.com directly.