What Is CSS Minifier?
CSS Minifier is a free browser-based tool that strips unnecessary whitespace from CSS to create smaller output. After you run it, a success message reports the approximate size savings as a percentage.
Use this minify css online tool when you want a compact stylesheet for a small project, a code snippet, or storage. It is built for one task: turning readable CSS into a smaller version quickly.
The minifier runs in your browser, so you do not need to install a build tool for a quick job.
How to Use CSS Minifier
Step 1: Add Your CSS
Paste CSS into the editor, load the sample, or import a .css file.
Step 2: Run the Minifier
Click Minify to remove unnecessary whitespace and generate compact CSS.
Step 3: Check the Size Savings
Read the success message, which shows approximately how much smaller the CSS is.
Step 4: Download
Download the minified result as a .css file.
CSS Minifier Features
- Minify CSS in the browser
- Strips unnecessary whitespace for smaller output
- Approximate size savings shown in the success message
- Paste, sample, or file import
- Download minified output as a
.css file
Common Use Cases
Shrink Stylesheets
Reduce the size of a stylesheet before storing it or adding it to a small project.
Compact Embedded Styles
Prepare CSS for use inside templates or snippets where smaller text is convenient.
Compare Before and After
Use the reported percentage to see how much whitespace was in your original CSS.
Quick One-Off Minify
Minify a single file without setting up a bundler or build pipeline.
CSS Minifier works with the following input and output:
- Input: CSS text (paste, sample, or file import)
- Output: minified CSS
- Download:
.css file
What It Does and Does Not Do
Here is what to expect from this minifier:
- Does strip unnecessary whitespace to make CSS smaller.
- Does run in the browser and report approximate savings.
- Does not guarantee identical computed styles for every exotic edge case.
- Does not bundle or concatenate multiple files into a project build.
Need readable CSS instead? Use CSS Formatter. For HTML, try HTML Minify or HTML Formatter; for JSON, see JSON Minifier. Preview your styles in HTML Viewer.
FAQ
Is CSS Minifier free?
Yes. Tools Viewer tools are free to use in the browser with no account required.
Do I need to create an account to use CSS Minifier?
No. Open the tool and start working — signup is not required.
Is my content uploaded to your servers?
No. CSS Minifier runs in your browser. Your content is not uploaded to Tools Viewer servers for this minify step. It stays on your device unless you download the result yourself.
Will minifying break my CSS?
Minifying removes whitespace. If your stylesheet uses unusual hacks, test your important pages after minifying.
What is the difference between the formatter and the minifier?
CSS Formatter beautifies CSS so it is easier to read. CSS Minifier is for producing smaller output.
Can it combine multiple CSS files?
No. It minifies the CSS you provide and does not bundle or concatenate files.
How do I minify CSS online?
Paste your CSS into CSS Minifier, click Minify, check the size savings, and download the result.
