AnyTool
Your files never leave your device. All processing happens locally in your browser.

How do I convert an Excel file to JSON?

Drop your .xlsx file into AnyTool's XLSX to JSON converter. It reads the spreadsheet in your browser and instantly outputs JSON — choose records, 2-D array, or column shape, keep numbers, dates and booleans as real types, then copy or download. Your file is never uploaded.

  • Records (array of objects), 2-D array, or column-array output
  • Preserves numbers, dates, and booleans instead of stringifying
  • Select any worksheet · pretty-print or minify
  • 100% in your browser — no upload, no signup, works offline

What is

XLSX to JSON Conversion

Converting XLSX to JSON turns an Excel spreadsheet's rows and columns into JSON — typically an array of objects where the header row supplies the keys. Type-aware converters keep numbers, dates, and booleans as real JSON values instead of strings.

File Conversion

Related terms

Excel to JSONSpreadsheet to JSONXLSX ParserJSON Records

How to Convert XLSX to JSON

Convert an Excel spreadsheet to JSON entirely in your browser, with full type preservation.

15 secWeb browser
  1. 1

    Upload

    Drop your .xlsx or .xlsm file onto the converter or click to browse. Nothing is uploaded.

  2. 2

    Choose shape

    Pick the JSON shape — records (array of objects), 2-D array, or column arrays — and select the worksheet.

  3. 3

    Tune output

    Toggle "Preserve data types" to keep numbers, dates and booleans, choose indentation or minify, and include or omit empty cells.

  4. 4

    Export

    Copy the JSON or download the .json file. Conversion is instant and updates live as you change options.

Result: A .json file or copied JSON text

Frequently Asked Questions

Yes — AnyTool converts in your browser, so the file never leaves your device.

AnyTool runs the entire conversion client-side using ExcelJS. The spreadsheet is read in your browser and never uploaded to any server, so there is no transmission or storage risk — even for sensitive financial or HR data.

Yes — type preservation keeps numbers, booleans, and dates as real JSON values.

With "Preserve data types" enabled, numeric cells become JSON numbers, true/false cells become booleans, Excel dates become ISO 8601 strings (or date-only / serial), and empty cells become null. Many online converters stringify everything instead.

No fixed limit — it is bounded only by your device's memory because there is no server.

Since processing happens locally, there is no per-file cap like the 2–5 MB limits common on free tiers of upload-based converters. Very large workbooks are processed in chunks so the page stays responsive.

Yes — pick any worksheet from the sheet dropdown.

Multi-sheet workbooks list every worksheet with its row and column counts. Select the one you want and the JSON updates live.

Detailed Explanation

Methodology

How XLSX to JSON Conversion Works

AnyTool parses the uploaded workbook in the browser with ExcelJS, reads the chosen worksheet cell by cell, and serializes the result with JSON.stringify. In records mode the header row becomes object keys (duplicate or empty headers are de-duplicated). Type preservation maps Excel numbers, booleans, and dates to native JSON values — dates as ISO 8601 — while blank cells become null.

  • Parsing runs client-side via ExcelJS — the file is never uploaded
  • Three output shapes: records (array of objects), 2-D array, column arrays
  • Preserves numbers, booleans, and dates as typed JSON; blanks become null
  • Output can be pretty-printed (2 or 4 spaces) or minified
  • Large sheets convert in chunks to keep the UI responsive
Privacy & Security

Privacy and Offline Use

Because conversion happens entirely in the browser, the spreadsheet never touches a server. The tool works offline after first load and has no fixed file-size limit beyond available device memory, unlike upload-based converters that commonly cap free-tier uploads.

XLSX-to-JSON: in-browser (AnyTool) vs typical online converters
CapabilityAnyToolTypical upload-based tools
File handlingProcessed in your browserUploaded to a server
PrivacyFile never leaves deviceStored on a server temporarily
Type preservationNumbers, dates, booleansOften stringified
File-size limitDevice memory onlyCommonly capped on free tier
Works offlineYes (PWA)No
Cost / signupFree, no signupOften limited or gated

Capabilities reflect the live AnyTool tool; competitor behavior varies by service.