Combine CSV Files
Append CSV files with matching headers into one download.
Choose XLSX or CSV, then load your worksheets. The first row is a header. Downloads contain values; original formulas and formatting are not preserved.
Working with many files? Open batch processing for supported operations. Batch uses its own basic options.
How to use Combine CSV Files
- Choose a supported file from your device. Spreadsheets are inspected automatically; choose the worksheet when the list appears.
- Set the options for this task: Input delimiter.
- Run the tool, review the result, and use the copy or download option provided.
What to expect
Choose XLSX or CSV, then load your worksheets. The first row is a header. Downloads contain values; original formulas and formatting are not preserved.
Local processing
Your files and inputs are processed in your browser and are not uploaded. Download or copy results before leaving. Normal site and library requests still reach the hosting service.
Frequently asked questions
What does Combine CSV Files do?
Append CSV files with matching headers into one download. Choose XLSX or CSV, then load your worksheets. The first row is a header. Downloads contain values; original formulas and formatting are not preserved.
Are my files or input sent to a server?
Your files are processed locally in your browser and are not uploaded. Text inputs and passwords also stay in the tool on your device. The hosting service still receives normal requests needed to serve the website.
Can I recover a result after closing the page?
Download or copy your result before closing or reloading. Optional local history stores tool names and activity counts, not your inputs, passwords, filenames, or results.