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Merge CSV Files by Matching Column Headers
Combine local CSV exports by column name, align reordered columns and download a single file with one header row.
Combine CSV files
Output files
Choose files or try the example to preview the output.
Getting started
Choose two to eight UTF-8 files with the same delimiter. Review the listed file order, merge, then check the preview before downloading.
Before you use the result
Each file allows 2 MiB, 10,000 data rows and 100 uniquely named columns. Merged output allows 100 columns, one million data cells and 8 Mi UTF-16 code units. Formula-like text is preserved.
Try an example
January has id,name and February has name,id,region. The merged file has id,name,region, with empty region cells for January.
How it works
Column names match exactly, including case and spaces. New columns appear in first-seen order. Missing columns get empty cells. Rows and duplicates stay in file order.
Frequently asked questions
Append local CSV exports even when their columns change order. Keep every field and download one CSV with a single header.
How do I use Merge CSV Files by Header?
Choose two to eight UTF-8 files with the same delimiter. Review the listed file order, merge, then check the preview before downloading.
Does this tool upload my data?
Inputs and files are processed in your browser. Page-view analytics do not contain your tool input.
What should I check before using the result?
Each file allows 2 MiB, 10,000 data rows and 100 uniquely named columns. Merged output allows 100 columns, one million data cells and 8 Mi UTF-16 code units. Formula-like text is preserved.