A JavaScript API needs objects.
Use CSV to JSON.
SPARKPOND / CATEGORY
Free Online Data Converters
Conversion changes representation, not meaning. These tools show typing, flattening, sheet and formula-safety decisions before export.
Problems covered
What you can solve
- ✓ Move CSV data into JSON APIs.
- ✓ Flatten nested JSON.
- ✓ Exchange data with Excel.
- ✓ Turn copied tabs into CSV.
5 tools
Tools in this category
Convert CSV to JSON Online
Convert CSV or TSV to JSON locally as objects, arrays or NDJSON. Control empty fields, numbers and booleans while preserving long IDs and leading zeros, no account needed.
Open →Convert JSON to CSV Online
Convert JSON arrays or NDJSON to CSV locally. Flatten nested objects with path notation, review arrays and missing keys, then download without an account.
Open →Convert CSV to Excel XLSX
Convert CSV or TSV to Excel XLSX locally with a chosen sheet name, practical widths, frozen headers and formula-safe text. Download without an account.
Open →Convert Excel XLSX to CSV
Convert Excel XLSX sheets to CSV locally without running formulas. Choose sheets, inspect cached values and dates, and download checked CSV files without an account.
Open →Convert TSV to CSV Online
Convert TSV files or tab-separated pasted text to CSV locally. Preserve quoted tabs and special characters, choose the output delimiter and download without an account.
Open →Choose well
Which tool should you use?
Nested API data must open in a spreadsheet.
Use JSON to CSV.
A workbook contains several sheets.
Use Excel to CSV.
Guides
Understand these problems
How to Convert Excel XLSX to CSV Without Excel
A browser can read XLSX values locally and serialize each selected sheet as a separate CSV.
Read →How to Flatten Nested JSON into CSV
Nested object paths can become columns, while arrays need a selected tabular policy.
Read →How to Preserve Leading Zeros in CSV Files
Leading zeros disappear when identifiers are interpreted as numbers rather than text.
Read →FAQ
Category questions
Are long identifiers preserved?
Yes. Text remains text unless a conversion is explicitly selected.
Are Excel formulas executed?
No. Only cached values are read and formula-like exports are protected.
Can nested JSON always become CSV?
Objects flatten well; nested arrays require an explicit serialization policy.