About CSV Toolkit
CSV Toolkit combines common spreadsheet cleanup and file-management tasks in one browser-local workspace. Clean one CSV, merge several files by header name, or split a large CSV into smaller files while keeping the source data with a simple workflow.
How to use CSV Toolkit
- 1
Choose Clean & Transform, Merge CSV or Split CSV.
- 2
Load one CSV file, or select multiple files when using Merge CSV.
- 3
For cleanup, remove duplicate rows, filter values, sort rows and choose or reorder columns.
- 4
For splitting, set the number of data rows to include in each output file.
- 5
Preview the result and download a CSV file or a ZIP containing the split files.
Tips for better results
- Merge works best when files use consistent header names; columns that are missing from one file are left blank.
- Use column selection before downloading when you only need part of a large dataset.
- Split large CSV files into smaller chunks when another service has row-count or upload-size limits.
Frequently asked questions
Which file formats can I use?
Check the file picker and tool description for the supported formats. Available formats can vary by tool.
Can I merge CSV files with different columns?
Yes. The toolkit builds a union of the header names and leaves missing values blank.
Does the splitter keep the header row?
Yes. Every generated split CSV includes the original column headers.