CSV to Excel

Double-clicking a CSV in Excel often goes wrong: everything lands in column A, leading zeros vanish from phone numbers and product codes, long numbers turn into 1.23E+15, and accented text becomes gibberish. Converting to a real XLSX file first avoids all of it.

This converter parses CSV and TSV files properly — quoted fields, commas inside quotes, line breaks inside cells — detects the delimiter automatically, and builds an Excel workbook. Numbers become real numbers you can sum, while values with leading zeros such as 0301 or 00123 stay as text.

Several CSVs can be combined into one workbook with a sheet per file, which is handy for monthly exports from the same system.

Column widths are set from the content, so the workbook opens readable instead of as a wall of truncated cells. The whole conversion runs in your browser, which means exported customer lists or transaction logs don't pass through anyone else's server on the way to becoming a spreadsheet.

How It Works

1. Add CSV/TSV files — up to 30. The parser follows RFC 4180: quoted fields, escaped double quotes and multi-line cells are handled correctly.
2. Set options — delimiter (auto-detect, comma, semicolon, tab, pipe), one workbook with a sheet per file or separate workbooks, type conversion, and whether the first row is a header.
3. Build the workbook — SheetJS writes a standard .xlsx with sensible column widths. Download it and open it in Excel, Google Sheets, Numbers or LibreOffice.

Compatibility & Support

Supported Input → Output Formats

• Input: .csv (comma or semicolon), .tsv, .txt with delimiters, UTF-8 or UTF-8 with BOM
• Output: .xlsx (Office Open XML), one or multiple sheets
• Typing: numbers and true/false converted; leading-zero codes kept as text

Unsupported Formats

Files in legacy encodings (Windows-1252, Shift-JIS) are read as UTF-8, so special characters may look wrong — re-save the CSV as UTF-8 first. Formatting such as colours, bold headers or frozen panes cannot come from a CSV because CSV contains none; add them in Excel afterwards. Dates are kept as text exactly as written to avoid day/month mix-ups between locales.

File Size Limits

Up to 30 files per batch and 60 MB each. Sheet names are limited to 31 characters by Excel, so long file names are shortened automatically.

Excel itself stops at 1,048,576 rows and 16,384 columns per sheet. A CSV bigger than that cannot fit in one worksheet in any tool; split it first or load it into a database or Power Query instead. Everything below that limit converts normally, though very large files take longer on phones.

Who Should Use This Tool?

• Students: A student converts CSV survey exports from Google Forms into a single workbook with one sheet per class section.
• Freelancers & Designers: A virtual assistant converts a client's exported contact list to XLSX so phone numbers keep their leading zeros.
• Office Professionals: An operations analyst merges twelve monthly CSV exports into one workbook with a sheet per month for a quarterly review.
• Developers: A developer hands a non-technical manager an XLSX version of a database export instead of a raw CSV.

Why This Tool Beats the Alternatives

• No “everything in column A” problem — the delimiter is detected properly.
• Protects leading zeros and long IDs from Excel's automatic reformatting.
• Merges many CSVs into one workbook in a single step.
• No upload of customer or financial data.
• Free, with no row or file-count paywall.

Pro Tips

• Phone numbers with a leading + or 0 stay as text — that's intentional, so they don't turn into scientific notation.
• If one column mixes numbers and text, leave “turn numbers into real numbers” on; text cells simply stay text.
• Need a quick printable view instead? CSV to PDF lays the table out on pages directly.

Drop your CSV files above and download a proper Excel workbook.