Fill Blank CSV Cells
Fill Blank Cells repairs gaps in the columns you choose. It covers two common cases: a grouped report export that labels only the first row of each team, and a form export where a skipped field should read N/A instead of staying empty.
A cell counts as blank when it is empty after trimming spaces. Columns you leave out are copied through unchanged, and the header row is never filled.
Key features
- Copy the last non-empty value above, or write a fixed value
- Fill selected columns or the whole file
- Unselected columns and the header row are left alone
About the CSV to CSV format
There are two modes. Last non-empty value above copies, for each blank cell, the nearest filled value higher up in the same column. Fixed value writes the same text into every blank cell in the selected columns. In the copy mode, blanks above the first filled value stay blank because nothing exists to copy. The column box takes comma-separated names matched to headers without regard to case; leave it empty to fill every column.
How it works
Rows are read from top to bottom. For each selected column the tool remembers the last non-empty cell it has seen. A blank cell in that column takes the remembered value in copy mode, or your fixed text in fixed mode. Every other cell is written back exactly as it was read.
Common use cases
- Restoring team names in a grouped timesheet where only the first row of each team carries the label
- Filling skipped shipping-country fields with a fixed placeholder before a bulk import
- Turning a sparse survey export into one value per row so a pivot table groups correctly
How to use this tool
- Paste the CSV or choose a file.
- Enter the columns to fill, or leave the box blank to fill all of them.
- Pick copy mode or fixed value, enter the placeholder if you chose fixed value, then click Fill.
- Check the output and download or copy it.
Example
Grouped timesheet with gaps (input)
team,member,hours
Ops,Priya,8
,Sam,6
,Dev,
Sales,Joe,
,Ana,4Columns filled: team, copy mode (output)
team,member,hours
Ops,Priya,8
Ops,Sam,6
Ops,Dev,
Sales,Joe,
Sales,Ana,4Tips for best results
- In copy mode, restrict the columns to the grouping fields. Filling every column copies the previous hours value into rows where nobody recorded any hours.
- Look at the first few rows before running. A blank in the first row of a column has nothing above it and will stay blank.
Common errors and how to fix them
- Column "zzz" was not found. Available columns: a, b.
- A name in the columns box does not match any header. Copy the exact header text from the list in the message, or check for a stray space or a missing comma.
- Enter the fixed value to fill blank cells with.
- Fixed value mode needs visible text such as N/A, 0 or UNKNOWN. Type one, or switch to copy mode.
Best practices
- Choose a placeholder that cannot be mistaken for real data, such as UNKNOWN, when someone will review the column later.
- Run the tool on one column first and spot-check a few groups before filling the whole file.
Choosing between copy and fixed value
Copy mode fits data where a blank means 'same as above'. Export tools often do this for merged cells, so the blank is a display artifact rather than missing information.
Fixed value fits data where a blank means 'unknown' or 'not applicable'. Writing a placeholder keeps those rows identifiable later, since a blank cell gives no way to tell 'unknown' from 'forgotten'.
Frequently asked questions
Are cells containing only spaces filled?
Yes. A cell holding only whitespace counts as blank and is replaced.
Can copy mode take its value from the row below?
No. It only looks upward. If each group's label sits at the bottom of its block, reverse the rows first, fill, then reverse back.
For more background on data formats and conversion workflows, read our format guides.