CSV Tools

Fill Missing Values

Replace empty cells with a default value

CSV Input

Try a sample:

Fill Value

CSV Output

Filled CSV will appear here...

More Options

CSV Format

Input

How to Use This Tool

Replace empty cells in your CSV with a default value. Any cell that is blank or contains only whitespace is treated as missing and replaced with the value you specify. This is useful for preparing data for systems that don’t handle empty values well.

  1. Provide your CSV — Paste CSV text into the input area, drop a CSV file onto the File tab, or enter a URL on the URL tab.
  2. Enter a fill value — Type the value to use for empty cells (e.g., N/A, 0, Unknown).
  3. Get your output — Copy the filled CSV to your clipboard or save it as a .csv file.

FAQ

3 questions
Does this tool upload my data?
No. It runs entirely in your browser using JavaScript. Your CSV data is never sent to a server.
What counts as a missing value?
Any cell that is completely empty or contains only whitespace characters is treated as missing and will be replaced with your fill value.
Can I fill different columns with different values?
This tool fills all empty cells with the same value. For column-specific fills, you can run the tool multiple times on extracted columns.

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