Split a Large CSV into Smaller Files

Split a large CSV into smaller files so Excel or an import tool can open them. Choose rows per file and download all parts as a ZIP. Free, no upload.

Quick answer: Combine many files into one, or split one file into many parts.

How to use the Split a Large CSV into Smaller Files

Combine many files into one, or split one file into many parts.

Merge or Split Files combines many CSV, JSON, Excel or Parquet files into one table, or cuts one big file into many parts. When merging, files are stacked one after another, with an optional source_file column. When splitting, you choose rows per file, a number of equal parts, or one file per value of a column, and download all parts as one ZIP in CSV, JSON, Excel or Parquet. It runs in your browser and nothing is uploaded.

Choose Merge or Split
Add your files and set the options
Download the result

Tips

Turn on source_file to see which file each row came from.
The header row is kept in every part when you split.
Very large files are limited by your computer memory.

Example

Input: big.csv (1,000,000 rows)

Output: files of 200,000 rows

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Who uses Data Utility

Frequently asked questions · Data format benchmark

Frequently asked questions

Why split a large CSV?

Excel opens about one million rows per sheet, and many import tools limit file size. Splitting makes each part easy to open and upload.

How large a file can I split?

It depends on your computer, because the file is read in your browser. Files up to about 100 MB usually work.

Can I merge CSV and Parquet files together?

Yes. You can mix CSV, JSON, Excel and Parquet files. They are stacked in the order you add them and saved in the format you choose. Columns missing in some files are left empty.

How do I split a big CSV file?

Load the file, choose rows per file, a number of equal parts or one file per value of a column, and download the ZIP. The header is kept in every part. Up to 500 parts at a time.

Merge or Split Files: CSV, JSON, Excel, Parquet: Combine many CSV, JSON, Excel or Parquet files into one, or split one big file into many parts. Free, and your files stay in your browser.
Combine Multiple CSV Files into One: Combine many CSV files into one file in your browser. Add a source_file column, mix in Excel or JSON files, and download CSV, Excel or Parquet. Free.
Merge Parquet Files into One: Merge several Parquet files into one Parquet, CSV or Excel file in your browser. No code and no upload. Free, with a source_file option.
Split a CSV File into Parts: Split a CSV into smaller files by number of rows, number of parts or the value of a column. Download them as one ZIP. Free, in your browser.
Split a Parquet File into Parts: Split a Parquet file into smaller Parquet, CSV or Excel files by rows, equal parts or a column value. Free, in your browser, nothing uploaded.

Topic guides

CSV Guides and Free CSV Tools