kube-score

kube-score is a static analyzer for Kubernetes object definitions, best suited to teams checking manifests before deployment or in CI/CD. Its configurable checks and flexible inputs suit varied workflows, while its results are strongest when related applications are analyzed together.

Overview

The project focuses on practical ways to improve the security and resilience of Kubernetes resources. Because it is MIT-licensed and free, teams can use it without a paid plan; its value depends on whether static checks fit their review process and whether they can supply enough namespace context for useful results.

Key features

Core checks cover container limits, security context, probes, stable APIs, NetworkPolicy targeting, PodDisruptionBudget and Pod anti-affinity. Optional checks add resource request-and-limit matching, container ports and seccomp profile configuration. Teams can enable optional checks or ignore tests globally or per object, making it possible to tune findings to a project’s needs. That flexibility is useful for varied deployments, though it puts responsibility on teams to decide which checks should apply.

Inputs can come from Helm, Kustomize, static YAML, Docker or resources retrieved from an existing cluster. The online demo accepts YAML or JSON, and the maker says processing happens entirely in the browser without sending data to a server. For ongoing use, prebuilt binaries cover Linux, macOS and Windows; Docker, Homebrew and Kubernetes Krew are also installation options. Building from source requires Go 1.21 or later.

In CI/CD, critical errors return exit code 1, and teams can instead set warnings as the failure threshold. Human-readable, JSON, CI and SARIF output support different consumers; SARIF is intended to simplify integration with CI platforms. This makes kube-score suitable for automated gates as well as manual review, with the chosen threshold determining how strictly a pipeline responds.

The main analysis caveat is scope: results are best when all applications deployed to the same namespace are included together. Reviewing isolated resources can therefore give a weaker picture of relationships among workloads and policies.

Pricing

Free and open source: free. The MIT-licensed tool has no paid plans, so there are no plan tiers, seat caps or trial terms to weigh. It is a straightforward fit for individuals and teams that can run and maintain the tool within their own workflows.

Platforms

kube-score is listed for Linux, macOS, Windows, self-hosted use and the web demo. Prebuilt binaries are offered for the three desktop operating systems; Docker, Homebrew and Krew provide additional installation paths.

Who it's for

Choose kube-score if you work with Kubernetes manifests and want configurable security and resilience checks before deployment, particularly if you can run it in CI/CD and analyze whole namespaces together. It is less suited to teams seeking a paid, supported service or a check that only evaluates a single isolated object without broader context.

Pros and cons

• Pro: Broad checks span resource settings, workload resilience, security context and API stability, giving teams several concrete review angles in one tool.
• Pro: Configurable checks, multiple input workflows and four output formats make it adaptable to both local review and CI pipelines.
• Pro: The browser demo runs locally in the browser according to the maker, which offers a quick way to inspect YAML or JSON without sending it to a server.
• Con: Stronger results require analyzing all applications in a namespace together, which can complicate review workflows that handle resources separately.
• Con: Building from source requires Go 1.21 or later, a setup requirement for teams that prefer not to use the prebuilt or packaged options.

Alternatives

For checks centered on Kubernetes configuration, kube-score is the direct fit among these choices. Pick kubeconform when you want a free tool focused on Kubernetes manifests; its listed platforms include Linux, macOS, self-hosted and Windows. For infrastructure policy work beyond Kubernetes, Conftest is a free, open-source option for Linux, macOS and Windows, while KICS is a free open-source option listed for Linux, macOS, self-hosted and Windows.

Readers evaluating other infrastructure checks can also consider AWS CloudFormation, cfn-lint, Chef InSpec, Cinc Auditor and OpenSCAP; each is a separate alternative with its own stated platforms and pricing model. Browse Infrastructure Testing Tools or Infrastructure as Code Security Software for more options.

Verdict

kube-score is a strong choice for Kubernetes teams that want a free, configurable static review step and can include namespace-level context in their analysis. Its checks, CI exit behavior and multiple formats support practical automation. Look elsewhere if your workflow cannot analyze related applications together or you need a paid service rather than a tool to incorporate into your own setup.