How to Open a CSV File in Windows (Notepad, Excel, PowerShell)

You can open a CSV file in Windows using Notepad, Microsoft Excel, or PowerShell.

CSV (Comma-Separated Values) is a plain-text format defined by RFC 4180. Each line is a record, fields are separated by commas, and fields containing commas, quotes, or line breaks must be enclosed in double quotes.

Opening a CSV in Notepad

Notepad is the simplest way to view a CSV file. Right-click the file, choose "Open with", and select Notepad. You’ll see the raw text, including commas and quotes.

Opening a CSV in Microsoft Excel

Excel automatically recognizes CSV files. Double-click the file or use File → Open and select the CSV. Excel will split the data into columns based on commas.

According to Microsoft Support, if your data isn’t splitting correctly, check that the delimiter is set to comma in the Text Import Wizard (for older Excel versions) or ensure the file has a .csv extension.

Opening a CSV in PowerShell

PowerShell can parse CSV files natively using the Import-Csv cmdlet. This correctly handles quoted fields and commas within quotes.

Import-Csv -Path "data.csv"

This returns a collection of objects where each object represents a row, and properties correspond to column headers.

Why Splitting on Comma Breaks Quoted Fields

A naive approach like splitting a string on commas fails when a field contains a comma inside quotes. For example, the line:1,"Smith, John",25 should be three fields: 1, Smith, John, 25. Splitting on commas yields four fields: 1, "Smith, John", 25.

Always use a proper CSV parser that respects RFC 4180 quoting rules. In Python, use the csv module; in PowerShell, use Import-Csv; in Excel, rely on the built-in import.