Remove Unnecessary Whitespace
Remove redundant spaces, tabs and line breaks to create compact stylesheets.
DEVELOPER TOOL / HTML
Free Online CSS Minifier
Reduce the size of your stylesheets with MoSanKit's free online CSS Minifier. Remove unnecessary whitespace, line breaks and comments to create compact CSS code that is easier to deliver to browsers.
✓ Quick, simple and free · No signup or installation required
CSS Minifier workspace
PASTE CSS · MINIFY · REVIEW SIZE · COPY OR DOWNLOAD
Original—
Result—
Saved—
Paste some CSS to get started.
HTML MINIFICATION WORKSPACEMOSANKIT / DEVELOPER TOOLS
THE BASICS
What Is a CSS Minifier?
A CSS Minifier is an online tool that reduces the size of CSS code by removing unnecessary characters such as redundant whitespace, line breaks and optional comments.
CSS minification makes stylesheets more compact without changing their intended styling rules. It is commonly used to optimize website assets and reduce the amount of CSS transferred to visitors' browsers.
BUILT FOR THE JOB
Key Features of MoSanKit CSS Minifier
Remove CSS Comments
Remove optional comments to reduce file size, with an option to preserve important comments.
Reduce CSS File Size
Compare the original and minified stylesheet sizes to see how much space has been saved.
Beautify Minified CSS
Convert compact CSS back into a readable structure with proper indentation and line breaks.
Preserve CSS Rules
Maintain selectors, declarations, media queries, variables and supported modern CSS syntax.
Copy or Download CSS
Copy minified CSS instantly or download the result as a .css file.
QUICK AND SIMPLE
How to Minify CSS Online
01 / ADD CSS
Paste your CSS
Enter your stylesheet into the input editor.
02 / MINIFY
Click Minify CSS
Remove unnecessary whitespace and optional comments.
03 / REVIEW
Review the output
Check the minified stylesheet and compare file sizes.
04 / EXPORT
Copy or Download
Copy the compressed CSS or save it as a CSS file.
WHY IT MATTERS
Why Minify CSS?
Large or unoptimized stylesheets can increase the amount of data browsers need to download. Minifying CSS removes unnecessary characters and helps reduce stylesheet transfer size.
This can support website performance optimization, especially when combined with other improvements such as image compression, JavaScript optimization, caching and efficient font loading.
MADE FOR EVERYDAY DEVELOPMENT
Who Can Use This Tool?
Frontend DevelopersValidate API responses and application data.
Backend DevelopersCheck HTML payloads and configuration files.
API DevelopersVerify request and response data.
QA EngineersValidate HTML during application testing.
StudentsLearn CSS code and structure.
GOOD TO KNOW
A few things, answered.
Quick answers about using the MoSanKit CSS Minifier.
Yes. You can minify CSS online for free without creating an account.
A correctly implemented minifier preserves CSS rules and their intended behavior. Always test the minified stylesheet before deploying it.
Minification reduces stylesheet transfer size, which can contribute to faster page delivery. The actual impact depends on the website and its overall performance.
Yes. The tool should preserve media queries and their associated CSS rules while removing unnecessary characters.
Yes. Use the preserve comments option when you need to retain comments in the output.
Formatting adds indentation and line breaks to improve readability. Minification removes unnecessary characters to create compact CSS.
If the tool processes CSS entirely in your browser, your code does not need to be uploaded to an external server.
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