CSV Byte Order Mark Tool
Add or remove the UTF-8 byte order mark so Excel opens your file correctly.
Fill in the form and press “Generate file” to see the result here.
How to use it
- 1Paste your CSV, or open the file in a text editor and copy it in.
- 2Adjust the delimiter and header options if the preview looks wrong.
- 3Adjust the options if you need something other than the defaults.
- 4Download the result, or copy it straight back into your spreadsheet.
About the CSV Byte Order Mark Tool
Excel does not assume UTF-8 when opening a CSV by double-click. Without a byte order mark it guesses the system code page, which turns accented characters and non-Latin text into mojibake.
The mark is three bytes at the very start of the file and is invisible in a text editor. It is also exactly what breaks other parsers, which read it as part of the first column name - which is why removing it is offered too.
Questions people ask
Is your data uploaded to a server?
No. This tool runs entirely in your browser using standard web APIs, so your data never leaves your device. You can confirm it by opening your browser's network panel while the tool runs, or by disconnecting from the internet after the page has loaded.
Is it free, and do I need an account?
Yes, it is free, and there is no account, no sign-up and no watermark on the result. The project is funded by optional donations.