Spreadsheet Converter
Upload any spreadsheet and convert it to XLSX, CSV, TSV, ODS, or JSON instantly. All processing happens in your browser — your files never leave your device.
Drop a spreadsheet here or browse
XLSX · XLS · CSV · ODS · TSV
About Spreadsheet Converter
Spreadsheet data rarely stays in one format. Data exported from a CRM arrives as CSV. An accountant sends an Excel XLSX file. LibreOffice users work in ODS. JavaScript applications need JSON arrays. Moving between these formats without the right tool means either opening heavyweight spreadsheet software or relying on server-based converters that upload your financial, client, or business data to unknown services.
Our Spreadsheet Converter uses SheetJS — the industry-standard JavaScript library for spreadsheet parsing and generation — to transform files between XLSX, XLS, CSV, TSV, ODS, and JSON formats with full fidelity. After uploading a file, the tool displays a table preview of the data so you can confirm the content before converting. Multiple sheets are supported, and you can select which sheet to export when converting a multi-sheet workbook.
The JSON output uses the first row as property names, producing an array of objects that can be fed directly into a REST API, database seeding script, or JavaScript application. The TSV format is useful when your data contains commas inside cell values (addresses, descriptions, names with initials) since tab-separated values avoid the CSV quoting complexity.
How to Use Spreadsheet Converter
- 1Click "Upload File" and select your spreadsheet — XLSX, XLS, CSV, TSV, ODS, or JSON.
- 2Preview the data table to confirm the content and column structure is correct.
- 3If the file has multiple sheets, select the one you want to convert from the sheet picker.
- 4Select the output format from the "Convert To" dropdown.
- 5Click "Convert" and then "Download" to save the converted spreadsheet file.
Use Cases
- →Convert Excel XLSX exports to CSV for data pipeline and ETL workflow processing
- →Export spreadsheet data as JSON for consumption by a REST API or JavaScript application
- →Open LibreOffice ODS files and convert them to Excel-compatible XLSX format
- →Transform CSV exports from databases or analytics tools into structured JSON objects
- →Convert a JSON data file to Excel for sharing with non-technical stakeholders
- →Change TSV files to CSV for compatibility with tools that only accept comma-separated input
Tips
- ✓The first row is used as property names when exporting to JSON — keep column headers clear and descriptive
- ✓TSV is ideal for data containing commas in cell values (addresses, product names with commas)
- ✓Large files with thousands of rows may take a few seconds to process in the browser
- ✓When converting to JSON, nested data from merged cells may need manual restructuring afterward
- ✓Use the demo file to explore the tool's behavior before uploading your own data
- ✓ODS files from LibreOffice convert cleanly to XLSX and maintain formulas in most cases
Frequently Asked Questions
You can upload files in XLSX, XLS, CSV, ODS, and TSV formats. Output formats include XLSX (Excel), CSV, TSV, ODS (LibreOffice), and JSON.
When you choose JSON as the output format, the converter uses the first row of the spreadsheet as the property names (keys) for each object. Every subsequent row becomes one object in the resulting array.
No — all conversion happens entirely in your browser using SheetJS. Your file is never sent to any server.
If the file cannot be parsed — because it is corrupted, password-protected, or in a format the tool does not support — an error message appears.
Yes. Since all processing happens in your browser, the practical limit depends on your device's available memory. Most spreadsheets up to several hundred megabytes convert without issues.
CSV (Comma-Separated Values) uses a comma to separate fields, while TSV (Tab-Separated Values) uses a tab character. TSV is often preferred when data contains commas.