What is CSV?
Basics of the comma-separated text format and tips for using it in your workflow.
CSV basics
CSV (Comma-Separated Values) is a plain-text format where data is separated by commas. One line is one record; columns are split by the delimiter, and the first line is often the header (column names).
Example
id,name,email 1,Alice,alice@example.com 2,Bob,bob@example.com
This makes it easy to exchange table-like data between Excel, databases, and web apps.
Why use CSV
- Portable: Opens in almost any OS or app; a common format for system integration.
- Lightweight: Smaller than binary formats; good for email and batch jobs.
- Readable: You can open and edit it in a text editor.
Delimiters
Although “CSV” implies comma (,), some regions or apps use semicolon (;) or tab. The CSV Checker can auto-detect or let you choose the delimiter.
Character encoding
CSV is text, so encoding matters. Common options:
- UTF-8: Standard internationally. With BOM, Excel often opens it correctly.
- Windows-1252 / ISO-8859-1: Common in older or regional systems.
Wrong encoding causes garbled text. See Encoding issues for more.
CSV vs Excel
Excel (.xlsx) is a binary format with cells, formatting, formulas, and multiple sheets. CSV is “plain table data” only—no formatting, one sheet per file. CSV is often used for data transfer; we compare them in CSV vs Excel.
Things to watch in CSV
- Duplicate IDs: Same ID in multiple rows can cause DB or matching errors. See Duplicate data guide.
- Invisible characters: Copy-paste or imported data may contain hidden control characters. CSV errors guide explains how to fix them.
- Column count mismatch: Rows with different column counts can break imports. Use format check to find them first.