Split CSV Files Online
Split CSV files into multiple smaller files by row count, directly in your browser.
How to split CSV files
- Drop your file onto the upload area. The tool loads it and shows the total row and column count.
- Enter the number of rows each part should hold in Rows per chunk. The default is 1000.
- Click Calculate chunks. A button appears for each part, labelled with its row range, for example Part 2 with rows 1,001–2,000.
- Click each part to download it. Every part is a separate file in the same format as the original, named with a _part1, _part2 suffix.
Your file is processed locally in your browser and is never uploaded. The free limit is 50 MB per file; larger files work if your device has the memory for them.
Worked example
An outdoor gear shop is uploading its catalogue to a marketplace that rejects files over a set row limit. Scaled down, the limit here is two products per file.
Input (CSV)
sku,title,price,in_stock
TR-100,Trail runner shoe,119,true
TR-101,Merino running sock,18.5,true
TR-102,Rain shell jacket,164,false
TR-103,Headlamp 400 lm,42.99,true
TR-104,Hydration vest,89,trueSettings
- Rows per chunk: 2
- Downloaded: Part 1 (rows 1–2)
Result
| sku | title | price | in_stock |
|---|---|---|---|
| TR-100 | Trail runner shoe | 119 | true |
| TR-101 | Merino running sock | 18.5 | true |
Five rows at two per chunk gives three parts: rows 1–2, rows 3–4, and row 5 on its own. Part 1 is shown. Each part has the full header and the rows in their original file order. The last part is smaller because the row count does not divide evenly. Nothing is dropped or repeated between parts.
Working with CSV files
Every CSV part starts with the same header line, so each one opens and imports as a standalone file. Parts are cut purely by row count, never by size in bytes. A column of long descriptions can make one part much larger than another, so choose a smaller chunk if an upload limit is measured in megabytes. A quoted field that spans several lines still counts as one row and is never split across parts. For a strict byte limit, try a chunk size, check the size of the first part, and adjust.
Values are written back as text. Blank and NULL cells both come out as empty fields. Fields containing a comma, quote or line break are wrapped in double quotes. Column names in the header follow the same rule, so a header such as "Size, cm" stays one column. Dates are written as YYYY-MM-DD, and booleans as true and false. Each part is UTF-8 with \n line endings and no byte order mark. Some older Excel versions need that mark to show accented characters correctly.
Frequently Asked Questions
Does every CSV part get the header row?
Yes. Each part begins with the column names, so any part can be imported on its own.
Can a multi-line CSV value be cut in half between two parts?
No. The file is parsed into rows before it is split, so a quoted value with line breaks stays inside one row and one part.
Can I split by a column value, such as one file per region?
Not with this tool, which splits by row count only. Filter the file once per value instead, or use the SQL Query tool.
Do I have to download each part separately?
Yes. Each part has its own download button and saves as a separate file. There is no single zip download.
Can I split a very large file?
Files up to 50 MB can be loaded on the free tier. The whole file is read into browser memory before splitting, so the practical limit also depends on your device.
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