First, work out which direction you need
People who search for "CSV to Excel" fall into two groups: those who want to open a CSV in Excel, and those who want to export an Excel workbook as CSV. The steps and the pitfalls are completely different, so decide which one you are before anything else.
| What you want to do | Terms that match | Section on this page |
|---|---|---|
| Open and edit a CSV in Excel | csv to excel / convert csv to excel / open csv in excel | 02 Import |
| Hand Excel data over as CSV | excel to csv / export excel to csv | 03 Save |
| Hand it over without garbled characters | csv utf-8 vs shift-jis | Dedicated encoding guide |
- Microsoft Support — Import text (.txt) or CSV files — the official import procedure
- Microsoft Support — Save a file under a different name — the official save procedure
Convert CSV to Excel (import)
Double-clicking is the one thing to avoid. Excel looks at the contents and guesses each column's type, so leading zeros vanish from product codes and 13-digit numbers turn into scientific notation such as 1.23457E+12. The correct procedure is below (it follows Microsoft's official import steps).
- Launch Excel and open a blank workbookDo not double-click the CSV. Start Excel first.
- Choose Data → From Text/CSVA file picker opens.
- Select the CSV fileA preview appears, with the delimiter and encoding detected automatically.
- Check the encoding under File OriginIf the preview looks garbled, switch to 65001: UTF-8 or 932: Shift-JIS.
- Turn off Data Type Detection, then set the columns you care about to TextProduct code and phone number columns must be Text. This is the heart of the leading-zero fix.
- Click Load, then save as .xlsx if you need toFrom that point on you can edit without damaging the source data.
Load it with Data → From File and keep the import as a Power Query query. Next time, one click on Refresh brings the data in with the same cleaning rules applied. Column types are pinned as well, so leading zeros cannot go missing again.
- Microsoft Support — Import text/CSV files — the primary source for these steps
Convert Excel to CSV (save)
- Activate the sheet you want to exportOnly one sheet is saved.
- Choose File → Save As
- Pick the file typeUse "CSV UTF-8 (Comma delimited)" for external systems, and "CSV (Comma delimited)" for legacy domestic business software.
- Convert the encoding afterwards if you need toOpen the file in Notepad, choose Save As, and set Encoding to ANSI to end up with Shift-JIS.
Most searches for "csv export" are about a system or a program writing out a CSV file. For exporting from Excel, use the steps above; for exporting from code, see the "Writing CSV" section of the reading and writing guide.
- Microsoft Support — Save As — the primary source for save formats
- Microsoft Support — CSV file format
Which format should you save in?
| Format | Encoding | Best for | Watch out for |
|---|---|---|---|
| CSV UTF-8 (Comma delimited) | UTF-8 (with BOM) | Web services and external tools | May still break in older Excel builds or some business systems |
| CSV (Comma delimited) | Shift-JIS (CP932) | Core business systems, accounting software, government filings | Emoji and some kanji are replaced with "?" |
| CSV (Macintosh) | Shift-JIS, CR line endings | Old Mac-only software | Rarely needed today, and a common source of garbled text |
If you are unsure, send UTF-8 first and switch to Shift-JIS only if the recipient sees garbled text. That is the modern default.
- Microsoft Support — CSV file formats — the official explanation of formats and encodings
- MDN — Encoding — the technical background to UTF-8
Top 5 conversion problems
| Symptom | Cause | Fix |
|---|---|---|
| Leading zeros disappear | The column was read as a number | Set the column to Text during import |
| Long numbers turn into scientific notation | Same cause (floating-point display) | Same fix. If the column is already damaged, re-import from the original file |
| Dates change (2026/1/5 becomes Jan 5) | Automatic date conversion | Turn off Data Type Detection |
| Only one sheet comes through | CSV supports a single sheet | Save each sheet separately |
| Formulas disappear | CSV stores values only | Keep the .xlsx for calculations and export a CSV copy for submission |
Lost leading zeros and scientific notation are not a display problem — the data itself has changed. Once you save over the file it cannot be recovered, so always rebuild from the original CSV.
- Microsoft Support — import procedure — the official description of data type detection
Converting large files
Excel's hard limit is 1,048,576 rows by 16,384 columns. A CSV bigger than that risks being truncated. Switch to one of the following instead.
- Power Query — pull only the columns and rows you need into Excel (workable up to a few hundred thousand rows)
- Python + pandas — read in chunks with
chunksize(code examples here) - A lightweight database such as DuckDB — query millions of rows directly with SQL
Frequently asked questions
Q.Do formats survive a CSV-to-Excel conversion?
No. CSV is plain text, so colours, bold text and column widths are not carried across. If the appearance matters, work in .xlsx instead.
Q.Is "csv to excel" the same thing?
Yes. It means either turning a CSV into the Excel format (.xlsx) or simply opening it in Excel. The steps are in section 02 of this page.
Q.How do I save Excel as CSV without garbling the text?
Save as "CSV UTF-8 (Comma delimited)". If the recipient runs a legacy system, choose Shift-JIS instead. For the full procedure see the dedicated encoding guide.
Q.Can I convert several sheets to CSV at once?
Not with the built-in features — it is one sheet at a time. The standard workaround is a VBA or macro loop that saves each sheet in turn.
Q.How do I check the row count after converting?
In Excel press Ctrl+End to jump to the last cell, in Power Query read the row count shown in the preview, and in code just count the rows.