.CSS file extension - Cascading Style Sheets
What is css file? How to open css files?
File type specification:
The css file extension is associated with Cascading Style Sheets (CSS). The css files are used to format the contents of web pages.
A css file contains customized, global properties and other information about how to display HTML elements. It can define the size, background, colors, fonts, line spacing, indentation, borders, formats and location of HTML elements.
Basically, the css files are used to create a similar look and feel across whole websites. The .css files are also used to reduce the amount of work and HTML code generated by consolidating display properties into one single file. The .css files are stored in a plain text format.
The style sheets have existed in one form or another since the beginnings of SGML in the 1970s. Cascading Style Sheets were developed as a means for creating a consistent approach to providing style information for web documents.
The Cascading Style Sheets (CSS) helps Web developers create a uniform look for several pages within a Web site. Instead of defining the style of each table and each block of text within a page's HTML, commonly used styles need to be defined only once in a CSS document.
Once the style is defined in cascading style sheet, it can be used by any page that references the .css file. What more, the CSS allows to easy change styles across several pages at once.
For example, a Web developer is able to change the default font size from 12pt to 14pt for ten pages of his Web site at once. If the pages all reference to the same style sheet, the text size only needs to be changed on the style sheet and all the pages will have their font changed.
While Cascading Style Sheets are great for creating text styles, they are really helpful for formatting other aspects of the Web page layout as well. For example, the .css file can be used to define the cell padding of table cells, the style, thickness, and color of a table's border, and the padding around images or other objects. CSS gives Web developers much more control over how their web pages will look compared what the HTML format offers. For this very reason, most internet pages today incorporate cascading style sheets.
The CSS specifications are maintained by the World Wide Web Consortium (W3C).
MIME types:
text/css is registered for use with CSS by RFC 2318.
Updated: January 2, 2025
The default software associated to open css file:
Company or developer:
Blumentals Software
Rapid CSS Editor enables users to quickly and easily create and edit cascading style sheets of any size and complexity.
Company or developer:
topstyle4.com
TopStyle is a powerful HTML5 & CSS3 editor for Windows. It contains powerful tools for building standards-compliant web sites.
Company or developer:
Adobe Systems Incorporated
Adobe Creative Cloud is latest member of Creative family. With this version Adobe moved from one-time fee to subscription based model, while no longer plans to offer one time purchase options like the users were used. There is either annual or monthly fee for using the whole bundle or just one program.
List of software applications associated to the .css file extension
Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open css file, edit css file, convert css file, view css file, play css file etc. (if exist software for corresponding action in File-Extensions.org's database).
Hint:
Click on the tab below to simply browse between the application actions, to quickly get a list of recommended software, which is able to perform the specified software action, such as opening, editing or converting css files.
Software that open css file - Cascading Style Sheets
Programs supporting the exension css on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about listed programs for open css file action.
Microsoft Windows:
Main software associated with css file by default:
Rapid CSS Editor
Top Style For Windows
Other suggested software:
Adobe Dreamweaver
NotePad++ text editor
ConTEXT
Sublime Text
PSPad
Web Page Maker
VbsEdit
CoffeeCup HTML Editor
Source Edit
