Drop your CSV file here
or click to browse
or paste CSV content
Ready to split
Load a CSV and configure chunk size, then click Split// divide a large csv into chunks by row count
Split large CSV files into smaller chunks by row count. Preserves headers, supports custom delimiters, and downloads all parts as a ZIP. Free, browser-based, no upload.
Drop your CSV file here
or click to browse
Ready to split
Load a CSV and configure chunk size, then click SplitDrop a .csv file onto the upload zone or paste raw CSV content into the text area.
Set how many data rows each chunk should contain. Pick a delimiter or enable auto-detect.
Click "Split CSV" and download individual chunks or all at once as a ZIP archive.
CSV File Splitter divides a single large CSV into multiple smaller files by row count. Each chunk optionally inherits the original header row, so you can feed each file directly into any tool without extra setup. Everything runs in your browser — no file is ever sent to a server.
No. All processing happens entirely in your browser using JavaScript. Your file never leaves your device, making this tool completely safe for sensitive or private data.
The limit depends on your browser's available memory. Most modern browsers handle files up to 200–500 MB comfortably. For very large files (1 GB+) consider using a command-line tool like split on Linux/macOS.
Yes — by default the "Include header row in each chunk" checkbox is enabled. This means every output file starts with the same header as your original CSV, so each chunk is independently usable.
The tool samples the first line of your CSV and counts occurrences of common delimiters: comma, tab, semicolon, and pipe. The delimiter with the highest count is selected automatically. You can override it manually by unchecking auto-detect.
Each chunk is saved as a standard .csv file (e.g. chunk_001.csv, chunk_002.csv). The ZIP download bundles all chunks into a single archive named after your original file.
Yes. The splitter is row-count based, not byte-based — it splits on newline boundaries while respecting quoted multi-line fields, so quoted values containing newlines are kept intact within their row.
Working with large CSV files is a common pain point for data engineers, marketers, and developers alike. Whether you're dealing with a 500,000-row database export, a multi-gigabyte analytics dump, or a mailing list too large for your import tool, splitting that file into smaller pieces is often the first step to getting work done. This free, browser-based CSV File Splitter makes that process instant and painless.
💡 Looking for premium web development assets? MonsterONE offers unlimited downloads of templates, UI kits, and assets — worth checking out.
Many tools impose hard limits on the number of rows they can accept. Email platforms like Mailchimp or Klaviyo cap list imports at 50,000–100,000 rows. Google Sheets maxes out at 10 million cells. CRMs like HubSpot or Salesforce have their own import quotas. Even command-line scripts sometimes time out or run out of memory when fed an entire 1 GB CSV at once.
By splitting your CSV into manageable chunks — say, 5,000 or 10,000 rows each — you can process each piece sequentially, work around tool limits, and recover more easily from partial failures. If one import batch fails, you haven't lost all your work; you just re-run that one chunk.
The tool reads your file entirely client-side using the browser's FileReader API. It never contacts an external server. Once the file is loaded, it identifies row boundaries by scanning for newline characters (\n), properly accounting for quoted fields that may span multiple lines. It then groups rows into chunks of the size you specify.
Each chunk is assembled as a new string in memory. If "Include header row" is checked, the first row of the original CSV is prepended to every chunk automatically. The resulting chunks are offered as individual file downloads or packaged into a ZIP archive using the JSZip library, which runs entirely in-browser.
A CSV file separates fields using a delimiter character. While comma is the most common (hence "comma-separated values"), real-world data exports frequently use tab, semicolon, or pipe characters instead. European locales often default to semicolons because commas are used as decimal separators. Database exports and log files frequently use pipe (|) to avoid conflicts with text that contains commas.
The auto-detect feature analyses the first line of your file and selects the most likely delimiter automatically. If your file uses an unusual delimiter or the detection guesses wrong, you can disable auto-detect and choose manually from the dropdown.
The most important feature of any CSV splitter is correct header handling. If you split a 100,000-row file into ten 10,000-row chunks but forget to include the header in chunks 2 through 10, every downstream tool will misidentify the first data row as column names — corrupting your import silently. This tool checks "Include header row in each chunk" by default, so every output file is self-contained and importable on its own.
The right chunk size depends entirely on your use case. Here are some common scenarios:
Unlike online file converters that upload your data to a remote server, this tool performs all processing inside your browser tab. Your CSV content is never transmitted over the network. This makes it appropriate for sensitive data: customer lists, financial records, healthcare exports, or any file governed by GDPR, HIPAA, or similar data-handling regulations.
The source code is transparent and auditable. No tracking pixels, no server logs of your file contents, and no account required.
If you need to automate CSV splitting as part of a pipeline, consider these command-line options:
split -l 10000 --additional-suffix=.csv input.csv chunk_ — fast but does not handle headers.pd.read_csv('file.csv', chunksize=10000) for memory-efficient processing.For one-off tasks or when you don't have a terminal handy, this browser-based splitter is the fastest option with zero setup.