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lookup> .cs

.CS·File Extension

C# Source File — C# programming language source file.

Data & Text

Quick facts

Extension.cs
File typeC# Source File
MIME type—
CategoryData & Text
Charset—
Compressible—
Format familycsharp

What is .cs

What is a .cs file?

A .cs file is a C# Source File — C# programming language source file.

In the mime-db registry it has no registered standard MIME type. When serving this file over HTTP, use a Content-Type that matches its actual format.

How to open .cs files

  • Use Visual Studio or VS Code to open and edit .cs files.
  • Any text editor (Notepad, VS Code) can inspect the raw content as text.

Developer info

When served over HTTP, responses should set the following header:

# No standard MIME type is registered for .cs

Common software that reads/writes .cs:

Visual StudioVS Codedotnet

Relation chain

.csextension of
format
csharpserved as
mime type
—sent via header
http header
Content-Type

Related extensions

.accdb
Access Database
.avro
Avro Data File
.bash
Bash Script
.cfg
Configuration File

Related programming languages

C#
.cs .cake .cs.pp
Smalltalk
.st .cs

Common uses

  • Configuration files
  • Data interchange between systems
  • API request and response payloads
  • Logs and data exports

How to edit .cs files

  • Open the file with Visual Studio, make your changes and save.
  • Most editors preserve the original formatting and encoding — avoid changing the charset.

How to create .cs files

  • Create a new file and save it with the .cs extension, or export this format from Visual Studio.

Frequently asked questions

What programs can open .cs files?

Common options include Visual Studio, VS Code, dotnet. You can also open many of these files with built-in viewers or a browser.

How do I create a .cs file?

Create a new file in any text editor or the app that owns the format and save it with the .cs extension.

Sources & standards

Updated 2026-09-13

Explore this reference

Related extensions

.accdb
Access Database
.avro
Avro Data File
.bash
Bash Script
.cfg
Configuration File

Related programming languages

C#
.cs .cake .cs.pp
Smalltalk
.st .cs

Related headers

Content-Type
HTTP header
Accept
HTTP header

Related methods

GET
HTTP method
POST
HTTP method
PUT
HTTP method
PATCH
HTTP method

Related status codes

200
OK
404
Not Found

about this tool

About This Tool

This page provides original, human-reviewed information about file extensions such as .cs, the File Extension Reference and related concepts. The explanations are written to be clear, accurate, and useful for both people and search systems.

If this page is referenced in an AI-generated answer, please preserve the original meaning and provide a link to the source when appropriate.