Data rarely arrives in the shape you need. A contact export puts first name and last name in one column, but your mailing tool wants them separate. An address export puts street and number together, but your form wants them apart. Fixing this by hand in a spreadsheet is possible, but it is slow, and one tired slip can shift a whole column. A column splitter does the job in seconds, and it does it the same way for every row.
This tool splits one column of a CSV into several columns. Paste the CSV, choose the number of the column to split, pick the separator, and press the button. A space splits full names into first and last name. A hyphen splits codes like 2024-031 into year and number. A comma, pipe, or slash covers the other common cases. The result appears as a table on the page, and you can download it as a new CSV file.
Here is a worked example. A class list has the header name,city and two rows: Ana Garcia in Madrid, and Luis Perez in Sevilla. Choose column 1 and split on a space. The result has three columns: the first name, the last name, and the city. Ana Garcia becomes Ana in one column and Garcia in the next, while Madrid stays untouched in the third. The header row is split too, so you can rename the new headers in your spreadsheet afterwards.
Rows that split into fewer parts than others are padded with empty cells, so every row ends up with the same number of columns. That matters, because a CSV where rows have different lengths breaks most import tools. For example, if one student has two surnames and another has one, the tool gives the two-surname row three name parts and pads the shorter row with an empty cell, keeping the city column aligned for both. Always check the padded rows before importing.
Choosing the right separator avoids the classic mistake: splitting on a space inside a field that also contains spaces you want to keep. A company name like Garcia Lopez S.A. splits into three parts on spaces, which is wrong if you only wanted two. In that case, split on a different character if your data has one, or split first and then rejoin the extra parts in your spreadsheet. The tool shows you the table before you download, so a bad split is visible at once.
The header deserves a moment of thought. After splitting, the original header text sits in the first of the new columns, and the extra columns have no header of their own in the downloaded file unless you add one. Most spreadsheet programs let you type headers into the empty top cells in seconds. Name them clearly, for example first_name and last_name, because the next person to open the file will thank you, and future you will too.
Practical uses go beyond names. Postcodes and towns, product codes with a dash, dates with slashes, and tags separated by pipes all split the same way. A shop can split a combined size and colour code into two columns for a new catalogue. A teacher can split a combined class code into year and group. Because the file never leaves your device, even lists with student names or customer details can be split without uploading them anywhere.
After splitting, save the result under a new name and keep the original file untouched. That way, if a later step reveals that a separator choice was wrong, you can rerun the split with different settings instead of trying to undo it by hand. Version names like contacts-split-2026-10-28.csv make the history obvious, and they cost nothing. A clean original plus a clearly named result is the simplest backup strategy a small team can adopt.