How is this different from CSV Slicer?

CSV Slicer extracts a single [start, end) range of rows and discards the rest. CSV Splitter covers the entire file, breaking every data row into consecutive, equal-sized chunks, each with the header repeated, rather than keeping just one slice.

Does every chunk include the header row?

Yes. Each chunk is a self-contained, valid CSV, the header row is prepended to every chunk's data rows, not just the first one.

What happens if the row count doesn't divide evenly by rows-per-chunk?

The last chunk simply contains whatever rows are left over, it will have fewer rows than the others rather than being padded or dropped.

Can I download all chunks at once as a zip?

Not currently, each chunk is shown and downloaded individually via the chunk selector and output panel, keeping the tool simple for now.

CSV Splitter - Break a CSV Into Equal-Sized Chunk Files

Overview

Introduction

A CSV that's too large to work with comfortably, or that needs to be uploaded in pieces to a system with row limits, often just needs to be broken into smaller, equal chunks.

CSV Splitter does exactly that: pick a rows-per-chunk count, and the whole file gets divided into consecutive chunks, each a valid, header-included CSV of its own.

What Is CSV Splitter?

A CSV chunking tool that divides all of a file's data rows into consecutive groups of a fixed size, repeating the header row in every resulting chunk.

It covers the entire input, unlike a range-extraction tool, every data row ends up in exactly one chunk.

How CSV Splitter Works

The input is parsed once via the shared CSV grid parser into a header row and data rows, then the data rows are walked in a simple loop, sliced into consecutive groups of the chosen size.

Each group is re-stringified back into CSV text with the header prepended, producing a list of independent, valid CSV chunks you can preview and download one at a time via the chunk selector.

When To Use CSV Splitter

Use this when a downstream system has a row limit per upload and you need to break a large CSV into pieces that each stay under it.

It's also useful for parallelizing work, splitting a big CSV into equal pieces so multiple processes or people can each handle one chunk.

Often used alongside CSV Slicer and CSV Editor.

Features

Advantages

Every chunk is a complete, valid CSV on its own, header included, ready to use independently.
Covers the entire file automatically, no need to compute ranges by hand for each piece.
The last, possibly-shorter chunk is handled correctly rather than silently dropped or padded.

Limitations

There's no combined "download all as zip" option currently, chunks are downloaded one at a time.
Very large inputs with many resulting chunks are all held in memory at once as an array of strings.

Examples

Splitting 5 rows into chunks of 2

Input

id,name
1,Ada
2,Alan
3,Grace
4,Linus
5,Margaret

Output

Chunk 1: id,name / 1,Ada / 2,Alan  |  Chunk 2: id,name / 3,Grace / 4,Linus  |  Chunk 3: id,name / 5,Margaret

5 data rows split at 2 rows per chunk produces three chunks, the last one shorter since 5 doesn't divide evenly by 2, each with the header repeated.

Best Practices & Notes

Best Practices

Check a downstream system's row limit before picking rows-per-chunk, so every resulting file safely fits.
Use CSV Size Analyzer on one chunk first if you also need to stay under a byte-size limit, not just a row limit.
Reach for CSV Slicer instead if you only need one specific range of rows, not the whole file divided up.

Developer Notes

splitCsvIntoChunks() parses the input once with parseCsvGrid, then walks the data rows (everything after the header) in a plain `for` loop stepping by rowsPerChunk, slicing out each consecutive group and re-stringifying `[header, ...chunkRows]` with stringifyCsvGrid; rowsPerChunk is validated as a positive integer up front, and a CSV with zero data rows returns a clear error rather than an empty chunk list.

CSV Splitter Use Cases

Breaking a large CSV export into pieces that fit a service's per-upload row limit
Dividing a big CSV into equal parts to distribute across multiple workers or people
Creating a handful of smaller sample files from one larger CSV for testing

Common Mistakes

Expecting a combined zip download, chunks are previewed and downloaded individually via the chunk selector.
Reaching for this when you actually just want one row range, that's CSV Slicer's job, not CSV Splitter's.

Tips

Use the chunk selector buttons to quickly page through and spot-check each piece before downloading.
Pair with CSV Editor if you need to touch up a specific chunk after splitting.

CSV Splitter