About SheetToolKit
Fast, private spreadsheet tools — 100% in your browser.
What is SheetToolKit?
SheetToolKit is a free suite of Excel and CSV utilities that runs entirely in your web browser. It was built for analysts, accountants, operations teams, and anyone who regularly works with spreadsheet data and values their privacy.
There is no account to create, no file size limit on the free tier for most operations, and no data ever sent to a server. Every calculation, comparison, and transformation runs locally using JavaScript — on your machine, in your browser tab.
Why in-browser processing?
Most online spreadsheet tools work by uploading your file to a cloud server, processing it, and streaming the result back. That means your data leaves your machine every time you use the tool — a real concern for financial models, HR data, client lists, and any other sensitive content.
SheetToolKit takes the opposite approach: your files are read directly by your browser using the SheetJS library. They never touch a network connection. You can even disconnect from the internet after the page loads and every tool will still work.
The tools
- Compare Excel Files — find every added, removed, and modified row between two workbooks
- Compare CSV Files — same diff engine, optimised for .csv files
- Merge Excel Files — combine multiple workbooks into one
- Split Excel — split a workbook by sheet, column value, or row count
- Remove Duplicates — deduplicate rows by any set of key columns
Pro plan
The free tier covers most everyday needs. SheetToolKit Pro (€39, one-time) removes row limits, unlocks multi-sheet comparison, side-by-side view, reconcile export, and batch processing. A lifetime license — no subscription, no renewal.
Built and maintained by
SheetToolKit is an independent project. Questions, feedback, and bug reports are welcome at the contact page.