In Excel: open the file via Data ▸ From Text/CSV (not by double-clicking), check the detected delimiter and column types in the preview, then Load.
On this page7
Open a blank workbook and use Data ▸ From Text/CSV to pick the .csv file.
In the preview, set the delimiter (comma, semicolon, tab) and File Origin/encoding if characters look wrong.
Click Transform Data to set column types — make ID-like columns Text so leading zeros survive.
Close & Load, then save the result as .xlsx. Or paste/upload the CSV into the converter above and download the .xlsx directly.
What this does
A .csv is plain text, not an Excel file — Excel merely knows how to display it. Double-clicking lets Excel guess the delimiter and data types, which is where mangled umlauts, stripped leading zeros, and dates like 1/2 turning into February 1st come from. Importing through Data ▸ From Text/CSV (Power Query) shows a preview where you control the delimiter, encoding, and per-column types before anything is loaded. The same idea underpins a lot of everyday Excel work, so the few minutes spent getting it right here pay back across every sheet you build afterwards. Treat it as a pattern, not a one-off, and it stops being something you look up and starts being something you reach for. The difference between a quick fix and a sheet you can trust is the extra minute you spend validating “insert csv excel”. Start on a copy or a tiny sample, keep the affected cells visible, and compare the result with the outcome you expected before you touch the real workbook. When this is a ribbon command, the selection matters more than the button: confirm the range, apply the command, then spot-check the output before saving. The point is a data step that keeps your analysis trustworthy, but the practical win is that someone else can open the file and understand what happened without asking you.
A worked example
A bank export orders.csv uses semicolons and contains the customer number 007. Double-clicked, Excel shows 7 in one column on some systems and everything-in-column-A on others. Imported via From Text/CSV with delimiter Semicolon and the customer column set to Text, it loads as 007 in its own column — then File ▸ Save As .xlsx makes it a real workbook. Almost every system exports CSV, and almost every recipient wants a clean spreadsheet. Controlling the import (or converting directly) prevents the classic silent data corruption: lost zeros, wrong dates, broken characters. If this is something you do often, add the command to the Quick Access Toolbar (right-click it on the ribbon and choose Add to Quick Access Toolbar) or learn its shortcut, so next time it is one click instead of a hunt through the menus.
In Google Sheets
This is a command rather than a formula, so there is no syntax to carry over. Google Sheets arranges its commands in menus across the top instead of a ribbon, names some of them differently and does not have every Excel command — look for the equivalent in the Sheets menus or its help before assuming the steps match. The aim was to get you unstuck fast and leave you a little more capable than a copy-paste would. The answer is at the top and the detail above shows why it holds — so the next time a colleague asks, you can answer without reaching for search. Treat “insert csv excel” as a routine rather than a one-off. Once you know which setting or command controls it, the same few steps handle every workbook where it comes up in Excel, and you can explain them to a colleague in a sentence.
Common mistakes
- Double-clicking the CSV and letting Excel guess the delimiter and types.
- Losing leading zeros because numeric-looking IDs were auto-typed as numbers.
- Broken ä/ö/ü because the file is UTF-8 but was read as ANSI — set File Origin to 65001: Unicode (UTF-8).
- Saving the imported data back as .csv and wondering where the formatting went — save as .xlsx.
Frequently asked questions
Is a CSV file an Excel file?
No. CSV is plain text with delimiter-separated values. Excel can open and display it, but features like formulas, formatting, and multiple sheets need .xlsx.
Why does my CSV open with everything in column A?
The file's delimiter does not match your system list separator (comma vs. semicolon). Import via Data ▸ From Text/CSV and set the delimiter explicitly.
Is the converter on this page safe for confidential data?
Yes — it builds the .xlsx entirely in your browser. Nothing is uploaded.