CSS Combiner
Merge two CSS files into one
CSS File 1
CSS File 2
Combined CSS
CSS Combining Examples
Paste two CSS files — one in each input editor — and the tool merges them into a single stylesheet:
Reset/base + component styles
Click Sample to load example CSS into both editors and see the merged result instantly.
What Is a CSS Combiner?
CSS projects often split styles across multiple files — reset, base, components, utilities. A CSS combiner merges them into a single file for production. Fewer HTTP requests mean faster load times. The W3C CSS spec defines the language; build tools like Vite and Webpack do this at build time. This tool gives you a quick dual-input editor right in your browser.
Paste your first CSS file into the top-left editor and your second into the bottom-left editor (or use Upload on each panel). The right panel auto-combines both inputs into one output. Everything runs in your browser — nothing is sent to a server. For formatting the result, use CSS Formatter. For minifying, use CSS Minifier.
How to Use This Tool
Paste or Upload CSS
Paste your first CSS file into the top-left editor and your second file into the bottom-left editor. Each panel has its own Upload button so you can load .css files individually. Use Sample to load example data into both editors at once.
Review Combined Output
The right panel auto-combines both inputs. File 1 appears first, followed by File 2. For validation, use CSS Validator. For adding vendor prefixes, use CSS Prefixer.
Copy or Download
Use Copy or Download to save the combined CSS. For converting SCSS or Less first, use SCSS to CSS or Less to CSS.
Where CSS Combining Helps
Legacy projects or hand-crafted sites may have many CSS files. Combining them reduces requests and simplifies deployment. Bootstrap and Tailwind use build pipelines; this tool offers a quick manual option with two dedicated input panels. For extracting CSS from HTML, use CSS Extractor.
For formatting the combined output, use CSS Formatter. For inline styles (e.g., email), use CSS to Inline. For converting between preprocessors, use CSS to SCSS or CSS to Less.
Frequently Asked Questions
Is my data private?
Yes. Combining runs entirely in your browser. No data is sent to any server.
What if both files have the same selector?
The tool keeps both as-is. This is safe because CSS cascade means the last rule wins when specificity is equal — exactly how browsers handle multiple stylesheets. If you need advanced deduplication, use build tools like cssnano or PostCSS.
What about @import?
The tool combines the text as-is. It does not resolve @import URLs. Inline or paste the imported content manually if needed.
How do I upload files?
Each input panel has its own Upload button. Click it to select a .css file for that panel. File 1 goes into the top-left editor, File 2 into the bottom-left editor.
Order of files matters?
Yes. File 1 appears first in the output, then File 2. Later rules override earlier ones when specificity is equal. Arrange your files accordingly.