Dockerfile Formatter & Linter
Normalize Dockerfile instructions and catch common build mistakes before you ship.
Batch workspace
Format multiple files locally in one run.
How to use the Dockerfile Formatter & Linter
Paste code or file
Paste your raw DOCKERFILE text or upload directly.
Configure options
Choose indentation, dialect, or formatting preferences.
Format & export
Click format, then copy, download, or inspect in tree view.
What is a Dockerfile Formatter & Linter?
Normalize Dockerfile instructions and catch common build mistakes before you ship. This tool re-indents and organizes code according to standard style conventions while checking for syntax validity. Everything executes 100% inside your browser, guaranteeing zero latency and complete privacy for API keys, user tokens, and confidential database schemas.
Options Explained
| Option | Description |
|---|---|
| Output mode | Choose normalized Dockerfile output or a JSON report with diagnostics. |
Frequently Asked Questions
Does this tool build my Docker image?
No. It formats text and performs lightweight static checks without running Docker.
Which instructions are recognized?
Standard Dockerfile instructions such as FROM, RUN, COPY, WORKDIR, ENV, CMD, and ENTRYPOINT are recognized.
Does formatting change shell commands?
No. Arguments and commands are preserved; instruction names and whitespace are normalized.
What does the linter check?
It reports missing FROM instructions, unknown lines, and instructions without required arguments.
Is my Dockerfile uploaded?
No. Processing runs entirely in your browser.