How do I convert CSV to Excel?

Paste your CSV data into the input area, or upload an Excel file. Choose the conversion direction and click convert. Download the result as .xlsx or .csv.

Is my data sent to a server?

No. All conversion happens locally in your browser using the SheetJS library. Your data never leaves your device.

What CSV formats are supported?

Standard RFC 4180 CSV with quoted fields, escaped quotes, and custom delimiters. The parser handles quoted fields with commas, escaped quotes, and newlines within fields.

Can I convert large files?

Yes, within browser memory limits. For very large files (100MB+), consider splitting into chunks. The conversion runs entirely in your browser.

CSV ↔ Excel Converter | Complex To Easy

CSV ↔ Excel Converter

Convert between CSV and Excel (XLSX) formats instantly. Paste CSV text or upload an Excel file — conversion happens entirely in your browser.

Input

Paste CSV Data

Load Sample CSV

Output

Enter CSV data or upload an Excel file to see the converted output.

CSV ↔ Excel Conversion Guide

Supported Formats

CSV: RFC 4180 compliant — quoted fields, escaped quotes, commas in fields, newlines in quoted fields
Excel: .xlsx (Office Open XML) and .xls (legacy BIFF) formats
Encodings: UTF-8 for CSV; Excel files preserve original encoding

How It Works

CSV → Excel: Parses CSV using RFC 4180 rules, creates XLSX workbook with SheetJS
Excel → CSV: Reads workbook with SheetJS, exports first sheet (or selected sheet) as RFC 4180 CSV
100% Client-side: No data leaves your browser — all processing uses SheetJS (xlsx) library in WebAssembly

Tips

For Excel → CSV, the first sheet is used by default
CSV output uses RFC 4180 quoting (only when needed: commas, quotes, newlines)
Large files (>10MB) may take a few seconds to process
Date/time formats in Excel are preserved as ISO strings in CSV

Privacy

Your data never leaves your browser. No uploads, no server processing, no tracking. The SheetJS library runs entirely in your browser via WebAssembly.