Merge CSV Files

Merge CSV Files combines two CSV datasets into one. Choose to merge by rows or columns, preserve headers, and export the result instantly in your browser.

Paste your input above or import a file below.
No file chosen
Supported file types: .txt, .csv, .tsv, .log, .json, .xml, .md, .ini, .yaml, .yml, .html, .htm, .css
Total characters: 0
Options
Remove # comments
Remove // comments
Preserve blank lines

How to Use:

  • Paste your two CSV files into the input areas or load them using the Choose File buttons.
  • Pick how to merge them using the radio buttons:
    • Merge by rows adds the second CSV directly after the first.
    • Merge by columns lines up the rows from each file side-by-side.
  • Adjust the toggles to control how the merge works:
    • Turn on Include both headers to keep the headers from both inputs.
    • Use Trim values to clean up extra spaces around each cell.
    • Enable Fill missing with blanks to pad short rows so everything aligns.
  • The output updates immediately when you type or switch any setting, and it flashes to confirm the change.
  • Click Copy Output to send the merged CSV to your clipboard.
  • Select Export to File to download the final result.
  • Press Clear All to wipe both inputs, reset the toggles, and clear the counter.
  • Watch the Total characters count below the output grow as the result changes.

What Merge CSV Files can do:

Merge CSV Files is built for combining two datasets quickly, whether you’re joining lists, consolidating spreadsheets, or combining different exports. You can stack files vertically or align them horizontally, with complete control over headers, spacing, and formatting. It’s fast, flexible, and runs entirely in your browser. No need to clean or reformat the data manually just paste, merge, and export.

Example:

File 1:

name,age
Alice,30
Bob,25

File 2:

city,country
New York,USA
Los Angeles,USA

Merged by columns:

name,age,city,country
Alice,30,New York,USA
Bob,25,Los Angeles,USA

Common Use Cases:

Use Merge CSV Files when consolidating reports, merging exports from different systems, or joining partial datasets into one clean file. It’s ideal for data prep, analysis, and quick file edits no external tools needed.

Useful Tools & Suggestions:

Before merging, Validate CSV can help ensure both files line up structurally. And if you need to sort or clean the final result, run Sort CSV Rows right after combining.

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