convert-csv.com logo convert-csv.com

Split Text or CSV Files

Split large text or CSV files by number of rows, file size, or repeating header.

100% Secure - your files are processed in your browser and never sent to a server.
Drop your file hereor click to browseSupports CSV, TSV, or TXT files (.csv, .tsv, .txt) (Max 100MB)

Splitting large text or CSV files is a common requirement when working with data that exceeds import limits, transfer size constraints, or memory capacity. This tool splits files by row count, file size, or repeating header pattern. Split by row count divides the file into chunks of a specified number of rows (e.g., 1000 rows per file). Split by file size creates chunks that do not exceed a target size in MB or KB. Split by repeating header preserves the column header at the top of each output chunk, which is essential for CSV files that need to be imported as separate files. The tool processes files entirely in your browser, streaming the input through a Web Worker to handle files up to 100 MB. Output chunks are available for individual download or batch download as a ZIP archive. This is useful for chunking large CSV exports for database imports, splitting log files for analysis, or dividing datasets for parallel processing.

How to use the Split Files tool

  1. Load your file: Drag and drop your text or CSV file, choose a file from your file explorer, or paste content directly into the paste area.
  2. Choose split method: Select how to split: by number of rows, by number of equal parts, or by approximate file size.
  3. Set split parameters: Enter the value for your chosen split method (e.g., 100 rows per file, 5 parts, or 50000 bytes).
  4. Configure header option: Toggle whether to keep or prepend the header row in each split file (for CSVs).
  5. Split and download: Click the "Split File" button. Each split file is listed with its name and size for individual download.

Frequently asked questions

What splitting methods are available?
Three methods: split by row count (e.g., 1000 rows per chunk), split by file size (e.g., 10 MB per chunk), and split by repeating header (preserves the first row in each chunk).
Does each output chunk include the header row?
Yes. When using row-count or file-size splitting, the header row is automatically included at the top of each chunk. This ensures each chunk can be independently imported.
Can I download all chunks at once?
Yes. After splitting, you can download individual chunks or batch-download all chunks as a ZIP archive for convenience.
What is the maximum input file size?
The tool handles files up to 100 MB. The streaming parser processes the file in chunks, keeping memory usage stable regardless of file size.
Can I split a CSV without breaking rows?
Yes. The parser respects row boundaries when splitting by size, ensuring no row is cut across chunks. Each chunk contains complete rows.

Related tools