CSV is a simple file format used to store tabular data, such as a spreadsheet or database. Files in the CSV format can be imported to and exported from programs that store data in tables, such as Microsoft Excel or OpenOffice Calc.

CSV stands for “comma-separated values”. Its data fields are often separated, or delimited, by a comma.

Example spreadsheet data

For example, let’s say you had a spreadsheet containing the following data.

The above data could be represented in a CSV-formatted file as follows:

Sally Whittaker,2018,McCarren House,312,3.75 Belinda Jameson,2017,Cushing House,148,3.52 Jeff Smith,2018,Prescott House,17-D,3.20 Sandy Allen,2019,Oliver House,108,3.48

Here, the fields of data in each row are delimited with a comma and individual rows are separated by a newline.

Creating a CSV file

A CSV is a text file, so it can be created and edited using any text editor. More frequently, however, a CSV file is created by exporting (File > Export) a spreadsheet or database in the program that created it. Click a link below for the steps to create a CSV file in Notepad, Microsoft Excel, OpenOffice Calc, and Google Docs.

  • Notepad (or any text editor)
  • Microsoft Excel
  • OpenOffice Calc
  • Google Docs

Notepad (or any text editor)

To create a CSV file with a text editor, first choose your favorite text editor, such as Notepad or vim, and open a new file. Then enter the text data you want the file to contain, separating each value with a comma and each row with a new line.

Title1,Title2,Title3 one,two,three example1,example2,example3

Save this file with the extension .csv. You can then open the file using Microsoft Excel or another spreadsheet program. It would create a table of data similar to the following:

In the CSV file you created, individual fields of data were separated by commas. But what if the data itself has commas in it?

If the fields of data in your CSV file contain commas, you can protect them by enclosing those data fields in double quotes ("). The commas that are part of your data are kept separate from the commas which delimit the fields themselves.

For example, let’s say that one of our text fields is a user-created description that allows commas in the description. If our data looked like this:

To retain the commas in our “Notes” column, we can enclose those fields in quotation marks. For instance:

Lead,Title,Phone,Notes Jim Grayson,Senior Manager,(555)761-2385,“Spoke Tuesday, he’s interested” Prescilla Winston,Development Director,(555)218-3981,said to call again next week Melissa Potter,Head of Accounts,(555)791-3471,“Not interested, gave referral”

As you can see, only the fields that contain commas are enclosed in quotes.

The same goes for newlines which may be part of your field data. Any fields containing a newline as part of its data need to be enclosed in double quotes.

If your fields contain double quotes as part of their data, the internal quotation marks need to be doubled so they can be interpreted correctly. For instance, given the following data:

We can represent it in a CSV file as follows:

Player Name,Position,Nicknames,Years Active Skippy Peterson,First Base,“““Blue Dog””, ““The Magician””",1908-1913 Bud Grimsby,Center Field,“““The Reaper””, ““Longneck””",1910-1917 Vic Crumb,Shortstop,“““Fat Vic””, ““Icy Hot””",1911-1912

Here, the entire data field is enclosed in quotes, and internal quotation marks are preceded (escaped by) an additional double quote.

Here are the rules of how data should be formatted in a CSV file, from the IETF’s document, RFC 4180. In these examples, “CRLF” represents a carriage return and a linefeed (which together constitute a newline).

  • Each record (row of data) is to be on a separate line, delimited by a line break. For example: aaa,bbb,ccc CRLF
  • The last record in the file may or may not have an ending line break. For example: aaa,bbb,ccc CRLF zzz,yyy,xxx
  • There may be an optional header line appearing as the first line of the file with the same format as normal record lines. The header contains names corresponding to the fields in the file. Also, it should contain the same number of fields as the records in the rest of the file. For example: field_name,field_name,field_name CRLF aaa,bbb,ccc CRLF zzz,yyy,xxx CRLF
  • In the header and each record, there may be one or more fields, separated by commas. Each line should contain the same number of fields throughout the file. Spaces are considered part of a field and should not be ignored. The last field in the record must not be followed by a comma. For example: aaa,bbb,ccc
  • Each field may or may not be enclosed in double quotes. If fields are not enclosed with double quotes, then double quotes may not appear inside the fields. For example: “aaa”,“bbb”,“ccc” CRLF zzz,yyy,xxx
  • Fields containing line breaks (CRLF), double quotes, and commas should be enclosed in double quotes. For example: “aaa”,“b CRLF bb”,“ccc” CRLF zzz,yyy,xxx
  • If double quotes enclose fields, then a double quote appearing inside a field must be escaped by preceding it with another double quote. For example: “aaa”,“b"“bb”,“ccc”

Microsoft Excel

To create a CSV file using Microsoft Excel, launch Excel and then open the file you want to save in CSV format. For example, below is the data contained in our example Excel worksheet:

aaa,bbb,ccc CRLF

aaa,bbb,ccc CRLF zzz,yyy,xxx

field_name,field_name,field_name CRLF aaa,bbb,ccc CRLF zzz,yyy,xxx CRLF

aaa,bbb,ccc

“aaa”,“bbb”,“ccc” CRLF zzz,yyy,xxx

“aaa”,“b CRLF bb”,“ccc” CRLF zzz,yyy,xxx

“aaa”,“b"“bb”,“ccc”

Once open, click File and choose Save As. Under Save as type, select CSV (Comma delimited) or CSV (Comma delimited) (*.csv), depending on your version of Microsoft Excel.

After you save the file, you are free to open it up in a text editor to view it or edit it manually. Its contents resemble the following:

Item,Cost,Sold,Profit Keyboard,$10.00,$16.00,$6.00 Monitor,$80.00,$120.00,$40.00 Mouse,$5.00,$7.00,$2.00 ,,Total,$48.00

OpenOffice Calc

To create a CSV file using OpenOffice Calc, launch Calc and open the file you want to save as a CSV file. For example, below is the data contained in our example Calc worksheet.

The last row begins with two commas because the first two fields of that row were empty in our spreadsheet. Don’t delete them — the two commas are required so that the fields correspond from row to row. They cannot be omitted.

Once open, click File, choose the Save As option, and for the Save as type option, select Text CSV (.csv) (*.csv).

If you were to open the CSV file in a text editor, such as Notepad, it would resemble the example below.

As in our Excel example, the two commas at the beginning of the last line make sure the fields correspond from row to row. Do not remove them!

Google Docs

Open Google Docs and open the spreadsheet file you want to save as a CSV file. Click File, Download as, and then select CSV (current sheet).

  • See our CSV definition for further information and related links.
  • Computer file help and support.