CSV vs Excel

Format differences and what to watch when exchanging or checking data.

Format difference

CSV (Comma-Separated Values) is plain text with columns separated by a delimiter (usually comma). One line = one record; there’s no formatting, formulas, or multiple sheets—just data.

Excel (.xlsx) is a binary format with cells, formatting, formulas, charts, multiple sheets, and images. It’s built for editing and viewing in a spreadsheet app.

When to use CSV

When you edit in Excel and need to send data to another system, save as “CSV (Comma delimited)” or “CSV UTF-8,” then check the file here to avoid encoding or column issues.

Saving and opening CSV in Excel

Saving

Excel’s “Save As” → “CSV (Comma delimited)” often uses a regional encoding. For UTF-8, choose “CSV UTF-8 (Comma delimited)” so the file is UTF-8 BOM and works well with other systems and this tool. See Encoding issues for more.

Opening

UTF-8 CSV without BOM can open in Excel with garbled text or wrong columns. Use this tool’s encoding fix to convert to UTF-8 BOM first, then open in Excel.

Leading zeros

Excel drops leading zeros (e.g. 0123 → 123) when it treats a cell as a number. For codes or IDs that must keep leading zeros, set the column to “Text” in Excel or fix the CSV. The single-file check can help spot such issues.

What CSV doesn’t have (that Excel does)

CSV is data only. It does not store:

For data exchange and validation, CSV is often enough; when you need formatting or formulas, use Excel or use both as needed.

Summary

CSV = “plain table data”; Excel = “spreadsheet with formatting and multiple sheets.” For integration and checking, CSV is a good choice. Use What is CSV and CSV errors guide to confirm encoding, delimiter, and duplicates before use.

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