Free · No signup · Runs in your browser
Fill Blank Cells in a CSV
Carry the last value down, drop in a default, or zero-fill gaps - all client-side, no upload.
Carry the last value down, drop in a default, or zero-fill gaps - all client-side, no upload.
Fill empty cells in three steps. Everything runs in your browser; your CSV never touches a server.
Drop in a file or paste rows. The tool reads the header and column types in place - nothing is uploaded.
Choose which columns to fill (or leave empty for all), then select forward fill, a fixed value, or zero.
Download clean, RFC-4180 CSV with every targeted blank filled. A stat shows how many cells changed.
Empty cells break sorts, pivots, and joins. Filling them should be fast, predictable, and private.
Carry the previous non-empty value down a column - the standard fix for grouped exports where labels appear once per group.
Zero-fill numeric gaps or drop in a fixed placeholder like N/A so downstream tools stop choking on nulls.
All processing is client-side JavaScript. No upload, no account, no server logs - your data stays on your machine.
Output is strict RFC-4180: proper quoting for commas, quotes, and newlines, so the file opens cleanly everywhere.