Keep, drop, reorder or rename columns of a delimited file; split one cell column into several columns by a separator, merge several columns into one, or add a constant / row-index column.
The delimiter (comma, tab, semicolon or pipe) is detected automatically for every input.
Every step is applied to the live grid with an undo stack.
All processing happens locally in your browser — your data is never uploaded to any server.
Output delim:
— used for preview text and downloads
Input options:
Input CSV / TSV
Column operations
Operation:
Columns (by name):
comma-separated list in the order you want them kept
Column:
New name:
Column:
split separator
new column name prefix
Columns:
separator / new name
when removing, the merged column takes the position of the first source
New column:
name
value
Preview
paste or open a file to see the parsed grid — every operation updates this preview.
Keep / Drop: select columns by header name (or 0-based index) — keeping also lets you reorder, e.g. city, name.
Split: turns each cell into several cells on the separator and creates one new column per part (missing parts become empty cells); replace or keep the original column.
Merge: joins the chosen columns with a separator into one new column.
Add: appends a column with a constant value or a 1-based row index.
CSV output uses RFC-4180 quoting; line endings are CRLF. Downloads always use the delimiter selected above (Auto = the detected input delimiter).
CSV / TSV column operations — structure only
A column operation changes the structure of a delimited file — which columns exist, their order and their names — while every row’s data passes through untouched. That is the key difference from spreadsheet formulas or data cleaning, which rewrite cell values. Output is always RFC-4180 quoted with CRLF line endings, whatever the input flavour.
Split matches its separator literally — regex characters like | or * act as themselves. The “Auto” output delimiter mirrors the sniffed input; pick a fixed one for downstream tools.
