Back to Free Tools
FREE TOOLS
CSV Blank Cell Filler
Forward-fill exact empty CSV cells in selected columns, with explicit short-row padding and complete counts.
UTF-8 CSV or TSV, Pasted delimited text
Filled CSV, JSON fill and padding counts
Browser only
Runs locally in your browser. Your files, pasted content and generated output are not uploaded. Reset clears this tool’s working data.
This tool needs JavaScript. If it does not load, refresh the page and try again.
How to use this tool
- Paste CSV or choose a UTF-8 file and select Input delimiter.
- Enter unique one-based Selected column positions. Choose Fill mode; forward-fill is the default. For Literal, enter Literal fill value.
- Optionally enable Pad short rows and choose Protect spreadsheet formulas. Select Fill blank cells and download filled.csv plus fill-report.json.
Examples
Selected values empty, A, empty become empty, A, A in forward-fill mode; the leading blank remains unresolved.
Limitations
- 5 MiB input, 50,000 data rows, 500 columns, 500,000 cells including header, 64 KiB literal and 20 MiB combined output; 30-second processing limit.
- Literal paste follows native LF normalization. Empty literal is a no-change fill. Original-empty counts exclude padded fields; padded and selected-padded counts are separate.
- No back-fill, mean/median, interpolation or inferred null tokens. CSV quoting/line endings and selected spreadsheet protection normalize serialization.
Related tools
No items found.