XLSX to CSV and JSON converter
About XLSX ⇄ CSV / JSON
The XLSX converter turns Excel workbooks into CSV or JSON and builds XLSX files from CSV or JSON.
How it works
Workbook to text
Upload an XLSX file and choose CSV or JSON. You can pick a worksheet by name or by 1-based position. Without a choice, the first worksheet is used.
Text to workbook
Swap the direction to read CSV rows or a JSON array of objects or arrays. The sheet name is cleaned up to meet Excel's naming rules, then a compressed XLSX file is created.
Real binary downloads
Workbooks are read as raw bytes. Generated workbooks download as real XLSX files, not text renamed to .xlsx.
Frequently asked questions
Are formulas evaluated?
No. The converter reads the stored cell values. It does not run Excel's calculation engine or macros.
Can I choose a worksheet?
Yes. Enter its name, which is not case-sensitive, or a 1-based index when converting from XLSX.
Is my workbook uploaded?
No. Reading, generating and downloading all happen in your browser.
Sources & last verified
We checked this tool's behavior and the claims on this page against the specifications below on . The tool runs in your browser, so the output you see is exactly what the engine produced.
Found a wrong result or an outdated claim? Report an error and we will check it again.
JSON to Excel
cURL to Code
Data URI Encoder / Decoder
.env ⇄ JSON / YAML
INI ⇄ JSON / YAML / TOML
YAML ⇄ TOML