Code Comment Formatter
Turn plain text into code comments for many languages. Choose line or block style and a banner, for JavaScript, Python, HTML, SQL and more.
Last reviewed by the Radiatus Cloud team
Wrap text in comment syntax for your language of choice.
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Format text as code comments
This tool wraps plain text in the comment syntax of your chosen language. It supports double-slash line comments for JavaScript, C and Java; hash comments for Python, Ruby and shell scripts; slash-star block comments for C and CSS; HTML comment markers; double-dash comments for SQL; and a decorative banner box that frames the text with asterisks. Each line of your input is commented individually for the line styles, while the block, HTML and banner styles wrap the whole text.
This saves you from adding comment markers by hand, which is tedious for multi-line notes, licence headers and section dividers.
Where comment formatting helps
Developers frequently need to turn a paragraph of notes, a to-do list or a licence statement into properly formatted comments. Pasting documentation into source files, creating eye-catching section banners, and converting notes between languages are all quicker with a formatter. The banner style is popular for marking major sections of a file so they stand out when scrolling.
The commented output pastes directly into your code. Remember to match the style to the language, since using the wrong comment syntax will cause a syntax error. All formatting happens locally in your browser.
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Frequently Asked Questions
Which comment styles are supported?
Double-slash, hash, slash-star block, HTML markers, SQL double-dash, and a decorative banner box that frames the text with asterisks.
Does it comment each line separately?
For line styles like double-slash and hash, yes. The block, HTML and banner styles wrap the whole text in a single comment.
What is the banner style for?
It creates a framed box of asterisks around your text, useful for marking major sections of a file so they stand out while scrolling.
Will the output work in my language?
Only if you pick the matching style. Using the wrong comment syntax for a language will cause a syntax error, so choose the style for your file type.
Can I use it for licence headers?
Yes. Paste the licence text and choose a block or banner style to produce a tidy header to place at the top of your source files.
Privacy & Security
Everything runs in your browser; nothing is uploaded.
How to Use
Paste text, choose a language style, and copy the commented version.
Disclaimer: This tool is provided "as is" without warranty of any kind. Results are for educational and utility purposes.
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