CSV opens wrong in Excel? Here is how to fix it, in your browser

You get a CSV file, double-click it, and Excel crams everything into one column. Or the names with an é or ü suddenly look like hieroglyphs. Frustrating, and almost always the same problem: the file is technically fine, but the "packaging" is wrong for your Excel.

The CSV / Excel fix tool repairs exactly that packaging. You drop your CSV in, the tool detects what's wrong and converts it to a version that opens correctly straight away. Everything happens in your browser; your data is not uploaded.

What the tool does

The tool detects and repairs the three things that make a CSV "break" between systems:

• Separator: comma, semicolon, tab or pipe.
• Encoding: UTF-8, UTF-8 with BOM, UTF-16 or CP1252/ANSI.
• Line endings: CRLF (Windows/Excel) or LF (macOS/Linux).

You get a preview, can adjust the detection by hand if you want, and download the result as a CSV or directly as XLSX. The content stays the same, only the packaging is cleaned up.

Why your comma CSV opens wrong in Excel

Dutch (and many European) Excel installs use the semicolon as the separator, because the comma is the decimal mark there. Open an "international" comma CSV and Excel sees everything as one column. And without a UTF-8 BOM, that Excel often assumes the file is CP1252, which breaks é, ü and €. The fix: convert to semicolons plus UTF-8 with BOM, and it opens correctly in one go.

The pain this removes

• No one-column chaos. Your rows split neatly into columns.
• No broken accents. é, ü and € stay readable.
• No manual importing. No more text-to-columns wizard.
• No upload. Your data (customers, amounts, addresses) stays on your device.

How to use it

1. Open CSV / Excel fix and drop your CSV into the box, or paste the raw CSV.
2. Review the detected settings and the preview. Something off? Adjust the separator, encoding or line endings.
3. Download as CSV, or as XLSX to open straight in Excel. Tip for European Excel: set the separator to semicolon and leave "UTF-8 BOM" on.

Frequently asked questions

What does this tool actually "fix"? Three things: encoding, separator and line endings. Those are the three reasons a CSV from one system won't open in another. The content stays the same.

What's the difference between UTF-8 and UTF-8 with BOM? The BOM is an invisible marker at the start of the file. For modern tools it makes no difference, but Excel needs it to show accents correctly. Leave it on unless you know your tooling doesn't want it.

Does my data go to a server? No. The reading and conversion happen entirely in your browser. Nothing is uploaded.

Can I get an Excel file directly? Yes. Besides CSV you can download the result as XLSX, which opens in Excel without fuss.

---

Fix your file: CSV / Excel fix. No more one-column chaos, and your data stays yours.