Lint Dockerfiles against best practices with Hadolint-style rules, security checks, and fix suggestions.
Paste a Dockerfile to identify instructions that conflict with Hadolint-style best practices or common container security guidance. The linter reports questionable constructs and, where it has a supported remedy, provides a fix suggestion. It is useful for reviewing image build recipes before committing them. A clean result does not prove that the image builds, that copied files exist, or that the resulting container is secure. The tool evaluates Dockerfile text, not the completed image.
The input is Dockerfile source containing instructions such as FROM, RUN, COPY, USER, and CMD. The tool compares those instructions with its Dockerfile-oriented rule set and reports applicable findings. Hadolint-style describes the kind of maintainability, correctness, and safety checks performed. It does not imply identical rule coverage, diagnostic identifiers, or results across every version of Hadolint.
Security checks identify risky patterns that can be recognized from the Dockerfile itself, while fix suggestions describe a safer or clearer edit when one is available. Processing occurs in the browser, so the pasted source is not uploaded. The linter does not inspect built image layers, registry metadata, build-context contents, installed package vulnerabilities, or behavior that appears only when the container runs.
No. The stated behavior is Hadolint-style linting, so the tool can apply similar kinds of Dockerfile best-practice checks without promising identical output. Do not depend on exact rule codes, severities, configuration behavior, or version-specific coverage unless the displayed result explicitly provides them. Use the official Hadolint release when exact compatibility is required.
No. It can flag security-relevant patterns visible in the Dockerfile, but it does not establish the security of the resulting image. Package vulnerabilities, unexpected files, inherited base-image contents, exposed secrets, runtime privileges, and application behavior require separate build verification, image scanning, secret detection, and runtime testing.
The behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.
Format, validate, and beautify JSON with syntax highlighting and error detection.
Encode text or files to Base64 and decode Base64 strings back to their original form.
Format and indent SQL queries for better readability across all major dialects.
Convert HTML markup into clean Markdown syntax with support for tables and lists.
Write Markdown and see the rendered HTML output in real time with live preview.
Visualize unified diffs and patch files with color-coded additions and deletions.