A new format.
Without the busywork.
Convert spreadsheets and structured data locally in your browser. Select an Excel worksheet, inspect 100 preview rows and download the format you need.
Open Convert →Your files stay on your device. No account or upload to our servers.
Four formats. One straightforward workflow.
CSV & TSV
Choose delimiters, UTF-8 or UTF-16 input, headers and output encoding. Text stays text, including identifiers and dates.
Excel & JSON
Select a worksheet or flatten nested JSON objects. Preserve safe numbers and booleans where the format supports them.
CSV ↔ XLSX · CSV ↔ JSON · XLSX ↔ JSON · TSV ↔ CSV · TSV ↔ XLSX · TSV ↔ JSON
Know what changes.
Limits: 15 MiB input, 20,000 data rows, 100 columns, 250,000 cells, 12 million text characters. Additional XML, archive, nesting and output limits apply. Conversion runs in a cancellable local worker with a 30-second processing deadline.
Only the selected worksheet is exported. Excel formatting, charts and formula results are not reproduced. Dates are not guessed; large numbers that would be rounded are kept as text. CSV and TSV exports apostrophe-protect formula-like cells, including negative numbers.
Flattening uses escaped dotted paths. Arrays become JSON text cells; nested structure is not automatically reconstructed. Empty, missing and null cells cannot remain distinct in CSV, TSV or Excel.
Conversion questions
Can I convert all worksheets at once?
Select one worksheet per conversion. Other sheets are not combined or exported silently.
Will it calculate Excel formulas?
No. Formulas are retained as literal text. Styles and formatted date displays are not reproduced.
Can I clean the file first?
Use Metrillix Migrate to clean and review your dataset, then use Convert for the output format.