CSS File Type

- The quick facts

What are CSS files and how to open them

Are you having problems opening a CSS file or just wondering what they contain? We explain what these files are used for and show you software that we know can open or otherwise handle your files.

What is a CSS file?

CSS is an acronym for Cascading Style Sheet. Files that contain the .css file extension are used to format the contents of an associated Web page. While the CSS file format is most commonly associated with website pages that have been written in the HTML and XHTML programming languages, the format can also be applied to any type of XML document.

A CSS file contains the properties that define how the HTML elements of an associated Web page will be displayed, such as the color, font, size, line spacing, borders and other HTML elements.

CSS files are similar to template files, allowing users to create multiple websites featuring a similar look and feel without having to create each and every site from the ground up.

How to open CSS files

Important: Different programs may use files with the CSS file extension for different purposes, so unless you are sure which format your CSS file is, you may need to try a few different programs.

While we have not verified the apps ourselves yet, our users have suggested 10 different CSS openers which you will find listed below.

Last updated: December 15, 2021

Suggest another file format using extension CSS

While we know of one file format using the .CSS file extension, there may be more. It is widespread that different programs use files with the same file extension for very different types of data. Please let us know if you are aware of a different kind of .CSS file.

Various apps that use files with this extension

These apps are known to open certain types of CSS files. Remember, different programs may use CSS files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Adobe DreamweaverAdobe DreamweaverUser submitted
Microsoft Expression WebMicrosoft Expression WebUser submitted
Macromedia Dreamweaver MXMacromedia Dreamweaver MXUser submitted
Microsoft OfficeMicrosoft OfficeUser submitted
Microsoft Development EnvironmentMicrosoft Development EnvironmentUser submitted
Microsoft Web Platform ExtensionsMicrosoft Web Platform ExtensionsUser submitted
Crescent EveCrescent EveUser submitted
UltraEditUltraEditUser submitted
Aptana StudioAptana StudioUser submitted
Macromedia DreamweaverMacromedia DreamweaverUser submitted
We have not verified any software that we know for certain will work with CSS-files on Mac. If you know one, please use the 'Suggest a program' link below and tell us about it!
We have not verified any web services that we know for certain will work with CSS-files. If you know one, please use the 'Suggest a program' link below and tell us about it!