How to Create a CSV File in Excel

To create a CSV file in Excel, enter your data in a worksheet, then go to **File → Save As**, pick a folder, and choose **CSV UTF-8 (Comma delimited)** from the file-type dropdown. Click Save. Below are the exact steps plus the three quirks that bite most people.

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Step-by-step

  1. Put your data in a single worksheet. CSV stores one sheet only — extra tabs are discarded.
  1. Put column names in row 1 (optional but recommended).
  1. File → Save As (or File → Save a Copy on newer Mac Excel).
  1. Choose **CSV UTF-8 (Comma delimited) (*.csv). Avoid the older CSV (Comma delimited)** option — it doesn't preserve non-ASCII characters.
  1. Click Save. Excel warns about losing formulas and formatting; click Yes.

Three Excel quirks to know

  • Leading zeros disappear. 00123 becomes 123. Fix by formatting the column as Text *before* entering data.
  • Dates get reformatted. Excel rewrites dates to your system locale. Lock the format with TEXT(A1,"yyyy-mm-dd") or use Text format.
  • Long numbers get scientific notation. 12345678901234 may become 1.23E+13. Same fix — Text-formatted column.

Faster alternative: skip the worksheet

If you only need the CSV as test data, skip Excel entirely. CSV.si lets you define columns (UUID, name, email, geo, finance) and download a properly-formatted CSV in seconds — no Excel quirks, no manual cleanup.

Frequently asked questions

Which 'CSV' option should I pick in Save As?

Always 'CSV UTF-8 (Comma delimited)'. The plain 'CSV (Comma delimited)' option uses a legacy encoding that breaks accents and non-Latin characters.

Can I save multiple sheets as one CSV?

No. CSV is one table. Save each sheet to its own CSV, or use XLSX.

Related guides

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