SheetTool is a free online CSV editor for private spreadsheet work.
Open CSV, Excel, or JSON files, clean messy data, run formulas, build pivot tables, create charts, write SQL queries, validate columns, record macros, and export — all without sending your data to a server.
SheetTool workspace
Built for quick CSV cleanup, conversion, and review.
Use the tool
One spreadsheet workspace for many CSV jobs
Edit, clean, transform, validate, chart, query, merge, split, compare, and export — all in one browser tab with no sign-up or server involved.
One focused toolkit
Everything you need for day-to-day CSV and spreadsheet cleanup
Replace one-off converters and scattered tools with a single private workspace for editing, cleaning, analyzing, and automating spreadsheet work.
Edit and transform
Sort, filter, find and replace, apply formulas, regex transforms, and type casting on full columns.
Clean messy data
Trim whitespace, remove empty rows, deduplicate, validate columns, and detect inconsistencies.
Compare spreadsheets
Diff two CSV or Excel files side by side with color-coded change highlighting.
Merge and split
Combine multiple files into one or split large CSVs into smaller chunks for upload limits.
Pivot, chart, and query
Build pivot tables, create bar/line/pie/scatter charts, and run SQL queries against your data.
Automate with macros
Record cleanup sequences and replay them on new files. Auto-save keeps your session safe.
Simple workflow
From messy file to ready-to-share spreadsheet
SheetTool keeps import, cleanup, review, and export in one place so you can finish small data jobs quickly.
Open a file
Drag in a CSV, XLSX, XLS, or JSON file, or use sample data to try the editor instantly.
Fix the spreadsheet
Edit cells, clean columns, merge files, compare changes, and apply formulas in one workspace.
Export your result
Download the finished spreadsheet as CSV, Excel, or JSON with no server processing.
Supported formats
Convert between common spreadsheet and data files
Open the file you have, make the changes you need, and export the file your team or system expects.
CSV
Import, edit, clean, split, merge, and export
XLSX
Open Excel workbooks and export clean files
XLS
Support for legacy Excel spreadsheets
JSON
Convert structured JSON to spreadsheet rows
CSV to Excel /Excel to CSV /JSON to CSV /CSV to JSON
Your data stays on your device
This tool is designed for sensitive spreadsheets that should not be uploaded just to make a quick edit or conversion.
Files are parsed locally with client-side JavaScript.
Your spreadsheets are never uploaded to a server.
No account is required before you start editing.
There is no tracking or analytics added to the tool.
Who it's for
Built for people who work with spreadsheets regularly
If you frequently receive, clean, transform, or hand off CSV and Excel files, SheetTool replaces scattered one-off tools with a single private workspace.
Operations & data teams
Clean vendor exports, normalize data, validate before import, and track changes with changelogs.
E-commerce managers
Prepare product catalogs, fix price columns, merge supplier files, and split uploads for platform limits.
Analysts & consultants
Profile columns, build pivot tables, run SQL queries, create charts, and export polished reports.
Developers & engineers
Convert between JSON, CSV, and Excel. Use regex transforms, validate schemas, and inspect data fast.
Marketers & CRM admins
Deduplicate leads, validate emails, anonymize data for sharing, and automate cleanup with macros.
Anyone handling sensitive files
Process private data without uploading it. No accounts, no servers, no data leaving your device.
Learn more
See everything SheetTool can do
Read the full guide with detailed explanations, examples, and tips for every feature.
FAQ