Convert CSV to Excel (XLSX)

Convert CSV / TSV to Excel (XLSX) online: delimiter auto-detected, numbers become numeric cells, first row as header. Converted in your browser — nothing uploaded.

Files stay local .csv、.tsv、.txt Max 50MB
Drop files here, or click to choose
Supports .csv, .tsv, .txt · Max file size: 50MB

Options

What this tool does

CSV-to-Excel turns plain-text tables into real .xlsx workbooks: numbers become summable numeric cells, the first row works as a header, and Chinese stops being mojibake. When someone can only send CSV but you need to work in Excel, this one step is enough.

Three delimiters (comma / semicolon / tab) with auto-detection, quoted fields (including commas and newlines) parsed strictly per RFC 4180, and numeric text written as numeric cells ready for formulas. Conversion runs entirely in your browser.

How to use

  1. Drop the CSV The delimiter is auto-detected by default (the most frequent candidate in the first line); for European semicolon-style CSVs, set it manually.
  2. Toggle numeric conversion By default "12.5" and "-3" become numeric cells (summable); turn the toggle off for codes and phone numbers where leading zeros matter.
  3. Download the XLSX The output opens in Excel / WPS / Numbers directly; for the reverse direction use the XLSX-to-CSV tool.

FAQ

Why did my phone number lose its leading zeros?

With numeric conversion on, pure digits become numbers. For phones, IDs and codes, toggle it off or quote the field in the source CSV.

How does delimiter auto-detection work?

It picks whichever of comma/semicolon/tab appears most in the first line. For files whose fields contain commas, set the delimiter manually.

Does conversion alter my data?

Aside from numeric casting, nothing changes: content, row order and empty cells are preserved; toggle numeric off for verbatim text.

How large a CSV is supported?

Up to 50MB per file — hundred-thousand-row files convert in seconds; split anything larger first.

Can it produce multiple sheets?

One CSV maps to one sheet (Sheet1). For multi-sheet workbooks, convert separately and combine in Excel.

Is my file uploaded?

No. Parsing and writing run in a browser Worker; the file never leaves your device.

Limits

Three standard delimiters (comma / semicolon / tab) plus auto-detect; no complex dialects beyond single characters.

Single-sheet output; no formulas, styles or charts. Up to 50MB per file.

Input is parsed as UTF-8 (BOM tolerated); transcode GBK and other legacy encodings first.

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