What Is a CSV File?

By Online CSV Editor · Last updated: 2026-03-23

A CSV file is a plain-text file used to store tabular data. Each line represents one row, and each row contains values separated by a delimiter such as a comma, semicolon, or tab. CSV is popular because it is simple, portable, and supported by CRMs, ecommerce platforms, spreadsheets, databases, and APIs.

Quick answer

CSV stands for Comma-Separated Values.
It stores rows and columns as plain text, not as a formatted spreadsheet workbook.
It is best for imports, exports, and system-to-system data handoffs.
It does not store formulas, colors, multiple sheets, or spreadsheet styling.

What a CSV file looks like

A simple CSV usually starts with a header row, then one line per record:

name,email,plan,signup_date
Ava Kim,ava@example.com,Pro,2026-03-01
Luis Chen,luis@example.com,Starter,2026-03-02
Jordan Patel,jordan@example.com,Pro,2026-03-03

In that example, the header names are name, email, plan, and signup_date. Each later line is one row of data.

How CSV structure works

CSV is simple, but a few rules still matter. The delimiter tells the parser where one cell ends and the next begins. Quotes allow delimiters or line breaks to appear inside a cell. Encoding controls how text characters such as accented names or symbols are stored.

For example, a value like "Paris, France" must be quoted in a comma-delimited file, because the comma belongs to the data, not to the column split.

Why CSV is still widely used

Universal compatibility: almost every business tool can import or export CSV.
Human-readable text: you can inspect it without needing a complex file viewer.
Lightweight format: CSV files are usually smaller and easier to move between systems.
Script-friendly: CSV works well in ETL jobs, backend workflows, and data pipelines.

CSV vs spreadsheet files

CSV is best when you need a clean exchange format. Spreadsheet formats like Excel are better when you need formulas, formatting, charts, comments, or multiple sheets. If you want the practical tradeoffs, read CSV vs Excel differences.

Common CSV pitfalls

Different tools expect different delimiters, such as comma vs semicolon.
Quoted fields break if quotes are missing or escaped incorrectly.
Encoding mistakes can create characters like Ã© or �.
Spreadsheet apps can strip leading zeros or auto-convert IDs and dates.

When to use CSV

Importing contacts, products, orders, or inventory into another system.
Exporting reports for a downstream tool to process.
Sharing structured tabular data between different platforms.
Creating a lightweight file for QA, cleanup, or validation.

Quick tips before editing CSV

Keep an untouched backup of the original export.
Check delimiter and encoding before making edits.
Validate IDs, dates, and leading-zero fields after opening in a spreadsheet.
Test-import a small sample before using the full file.

FAQ

What does CSV stand for?

CSV stands for Comma-Separated Values, even though some CSV files use semicolons or tabs instead of commas.

Can I open a CSV in Excel?

Yes, but the safest approach is to import it with delimiter and encoding settings instead of double-clicking the file.

Why is my CSV not opening correctly?

The usual causes are wrong delimiter selection, encoding problems, or spreadsheet auto-formatting. Those are fixable once you know which issue you have.

Canonical: https://csveditoronline.com/docs/what-is-a-csv-file