EasyExtract
❤️ Donate

Convert JSON to Excel Online (XLSX & CSV)

Convert raw JSON files, API responses, or JSON arrays into clean Microsoft Excel (.xlsx) workbooks and CSV spreadsheets directly inside your browser. Analyze complex nested database exports and web payloads in Excel without uploading your confidential records to third-party servers. Paste JSON text or drop a .json file to recursively flatten nested keys and download your spreadsheet instantly.

Drop a .json file here
or paste JSON text into the box below · 100% private in-browser

Understanding JSON to Excel conversion and data flattening

JSON (JavaScript Object Notation, RFC 8259) is the dominant data interchange format across modern web APIs, microservices, and NoSQL databases. Unlike tabular formats, JSON represents information as deeply nested hierarchical key-value pairs and arrays. Microsoft Excel and relational databases, however, operate on a two-dimensional grid composed of rows and columns.

Transforming JSON into Excel requires hierarchical flattening. When an object contains nested child objects (such as {"user": {"address": {"city": "Berlin"}}}), EasyExtract inspects the document tree and constructs a compound header using dot notation: user.address.city. Array values (such as list of roles or tags) are serialized into clean, semicolon-separated cell values to preserve data integrity without creating duplicate row fragmentation.

Most online converters transmit your files to remote web servers where sensitive data may be cached or logged. EasyExtract executes 100% inside your client device's browser memory (RAM) using standard HTML5 APIs and generates valid ECMA-376 OpenXML (.xlsx) binaries locally. Your confidential client records, API credentials, and internal metrics never leave your computer.

How to convert JSON to an Excel spreadsheet

  1. Upload or paste JSON data. Drop your .json file onto the upload zone or paste your raw JSON string or API payload into the editor.
  2. Enable automatic nested flattening. Leave 'Flatten nested keys' checked to automatically convert deep hierarchical structures (like user.address.city) into dedicated spreadsheet columns.
  3. Click Convert to Excel. The client-side engine parses the data in local browser memory and compiles the table structure in milliseconds.
  4. Download XLSX workbook. Click 'Download Excel (.xlsx)' to save a native Microsoft Excel file, or choose CSV / TSV to import into Google Sheets.

Frequently asked questions

How do I open a JSON file in Microsoft Excel?

You can convert the JSON file to a native .xlsx workbook using EasyExtract in your browser with zero uploads. Alternatively, inside Microsoft Excel, navigate to Data > Get Data > From File > From JSON to import it using Excel's Power Query engine.

Can this tool handle deeply nested JSON objects?

Yes. The built-in flattening engine recursively scans all nested levels and converts nested properties into clear dot-notation columns (e.g. customer.billing.zipcode). Arrays of primitive values are cleanly joined with semicolons.

Is my JSON data uploaded or stored on your servers?

No. EasyExtract runs 100% client-side in your browser's JavaScript engine. Not a single byte of your JSON data or generated Excel workbook is ever uploaded to a server or external cloud API.

Does it support JSON Lines (NDJSON)?

Yes. You can paste standard JSON arrays, single JSON objects, or line-delimited JSON (NDJSON) exports from systems like Elasticsearch, MongoDB, or CloudWatch.

What is the maximum file size for conversion?

Because all processing takes place in your local computer's memory, EasyExtract can easily process tens of thousands of rows and multi-megabyte JSON payloads without server timeouts or file-size paywalls.

Reviewed by Shah Abrar Ahmad & the EasyExtract Engineering Team • Specialist file parsing & security engineer • Verified: in our experience, our hands-on testing measured and verified private in-browser execution with zero file uploads • Last reviewed October 2026.