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Convert semicolon-delimited CSV to comma

European Excel exports use semicolons. Many tools expect commas. Upload your file — CSViser auto-detects the delimiter and converts it in one click, safely re-quoting any values that contain a comma.

Upload your semicolon or tab-delimited file

CSV, XLSX, or JSON — any size

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After upload: go to Fix issues tab → check Convert delimiter to comma → Apply.

Why does Excel use semicolons instead of commas?

CSV stands for "comma-separated values", but the RFC 4180 standard doesn't actually mandate commas — it just defines the quoting and line-ending rules. Microsoft Excel uses the system list separator from Windows regional settings as the CSV delimiter. In most European countries, the decimal separator is a comma (1.234,56), so Windows uses a semicolon as the list separator to avoid ambiguity. The result: a file named export.csv that contains semicolons and opens correctly in European Excel but breaks every tool that expects commas.

Tab-delimited files (.tsv) have the same problem in a different form — they're often renamed .csv by exporters, then handed off to tools that parse commas. Pipe-delimited files (|) appear in database dumps and legacy mainframe exports.

How the conversion works

CSViser uses a quote-aware delimiter detector (similar to Python's csv.Sniffer but with better handling of multi-line quoted fields) to identify the actual delimiter used in your file. It then parses the file correctly with that delimiter and re-serialises it with commas, automatically quoting any cell values that now contain a comma — so a value like Smith, John becomes "Smith, John" in the output, fully RFC 4180 compliant.

The conversion is non-destructive: numbers, dates, and all other cell contents stay exactly the same. Only the delimiter character changes.

Supported input delimiters

  • Semicolon (;) — European Excel exports
  • Tab (\t) — TSV files, database dumps
  • Pipe (|) — legacy data exports, mainframe systems
  • Comma (,) — already correct; no conversion needed

Frequently asked questions

My values contain semicolons — will they survive the conversion?

Yes. CSViser parses the file first, treating your values as opaque strings. Only the delimiter between cells is changed; content inside cells is preserved. If a cell contains a comma after conversion, it is automatically surrounded with double quotes per RFC 4180.

Can I convert comma-separated to semicolon instead?

This tool converts to comma (the universal standard). If you specifically need semicolons for compatibility with a European Excel installation, use the Search & Replace tab in CSViser to do a custom delimiter swap — or reach out via the contact page.