CalcBrew

Converters

Data & Spreadsheets

CSV, XLSX, JSON and ODS — convert between data formats. · 9 tools

Spreadsheets and data files are where small conversion mistakes cost real time: a leading zero dropped from a postcode, a date flipped to the wrong month, a semicolon-separated file crammed into one column. These tools detect delimiters and encodings, keep text as text unless it is clearly numeric, and write ISO dates.

Everything runs in your browser, so exports containing customer or financial data never leave your computer. Files with hundreds of thousands of rows are fine on a desktop.

How to choose

From a system export to Excel
CSV to Excel handles separators, quoting and encodings that Excel’s own import gets wrong.
From a spreadsheet to code
Excel to JSON or CSV to JSON produce typed arrays of objects; JSON to Excel goes the other way with nested fields flattened into columns.
Between office suites
ODS to XLSX and XLSX to ODS keep formulas and formatting; XLS to XLSX modernises old files.

Frequently asked questions