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Data · Best format for…

Best Spreadsheet Format for Data Exchange

Spreadsheets fail at boundaries — encoding, delimiters, and formulas that are not values. Pick CSV for machines and XLSX for people.

Quick take: CSV for values and pipelines. XLSX when humans need sheets, formulas, and formatting. TSV when commas fight your data.

Formats to consider

CSV

Best machine interchange

Ubiquitous imports/exports.

Pros

  • Universal
  • Simple

Cons

  • No formulas/formatting

XLSX

Best human workbook

Excel/Sheets business default.

Pros

  • Formulas
  • Multiple sheets

Cons

  • Heavier for ETL

TSV

Best when fields contain commas

Tab-separated values.

Pros

  • Fewer comma collisions

Cons

  • Less common than CSV

JSON

Best for nested API data

Not a sheet — convert when flat.

Pros

  • Structured

Cons

  • Needs flattening for CSV

ODS

Open workbook alternative

LibreOffice-first.

Pros

  • Open standard

Cons

  • XLSX more common in business

Recommendations by situation

Database or Python import

Pick: CSV (UTF-8)

Clean values, easy parsers.

Finance model for a teammate

Pick: XLSX

Formulas and formatting.

API dump to analysts

Pick: JSON → CSV

Flatten then sheet.

Legacy .xls file

Pick: Move to XLSX or CSV

Modernize.

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Related comparisons

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FAQ

Why did Excel mojibake my CSV?

Encoding mismatch — prefer UTF-8 and use the import wizard when needed.

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