CSV Cleaver
Split large CSV files into smaller files that Excel can open.
macOS · Windows · Linux — every installer carries its own Java runtime.
cleave /kliːv/ verb
- to split or divide, especially along a natural line.
- to cling or hold fast to.
One word, two opposite meanings — a contranym. This application does the first to your file and the second to your rows.
Byte-faithful
Concatenating the output reproduces the input, byte for byte. Tested on every build, and the tests themselves are mutation-checked.
Nothing overwritten
No file on disk is ever replaced without consent — collisions are detected and asked about, never assumed away.
Private by design
Your data never leaves your machine. No accounts, no telemetry, no network access to split a file.
Eight languages
English, Spanish, French, German, Italian, Portuguese, Chinese and Japanese — numbers formatted correctly in each.
A REST API too
Run it headless with --api and script it: async jobs, uploads, a Swagger page. API docs.
Honest about itself
Written predominantly by an AI under human direction, and it says so — with a verification ledger of what is proven and how.
Privacy
This site is static files served by GitHub Pages: no cookies, no analytics, no tracking scripts. Your browser makes one request to GitHub's API, to show the latest version number on the download button; pages served from github.io appear in GitHub's ordinary server logs, covered by the GitHub Privacy Statement. The google-site-verification tag in the page header is an inert ownership proof for search indexing — it loads nothing and reports nothing about you. The application's own privacy promises are stronger still: see the user guide.