Turn Excel Into Clean JSON. Nested. Typed. Offline.

Sheet2JSON converts Excel and CSV files to developer-ready JSON on your own PC. Headers like customer.name become nested objects, not another flat dump. Nothing is uploaded.

Nested objects and arrays, straight from your headers
JSON-LD, NDJSON, JSON, CSV and more: 8 output formats
Your files never leave your PC

Try Sheet2JSON for free

10 free conversions, everything unlocked. No credit card, no sign-up. Windows 10 & 11.

Files uploaded, ever

Output formats, incl. JSON-LD

Live preview

Check your JSON as you select

14 days

No-questions refund

Your headers describe the structure. Sheet2JSON builds it.

Every free converter dumps flat rows and leaves the real work to you. Put dots and brackets in your headers, and Sheet2JSON emits the JSON your code actually wants.

Your spreadsheet

id	customer.name	customer.city	tags[0]	tags[1]	active
A-101	Alpenglow GmbH	Köln	retail	eu	TRUE
A-102	Cobalt Retail	Wien	b2b		FALSE

Sheet2JSON output, nested mode

[
  {
    "id": "A-101",
    "customer": {
      "name": "Alpenglow GmbH",
      "city": "Köln"
    },
    "tags": ["retail", "eu"],
    "active": true
  },
  …
]

Convert on your PC, not on someone's server

Web converters want your workbook uploaded first, and then hand back flat rows with the types guessed wrong. Sheet2JSON does the whole job on your own computer.

Free web converters

Your workbook goes to a server you do not control
Flat rows only: nesting is your problem
Types guessed wrong: ID 007 becomes the number 7
One small file at a time, one selected sheet
Copy, paste, repeat, for every single export

Sheet2JSON

Everything happens on your PC, offline
Nested objects and arrays from dot and bracket headers
Per-column types: 007 stays "007", TRUE becomes true
Combine worksheets in one file, or export a selected range
JSON-LD with your context, NDJSON for pipelines

What you need

A Windows PCWindows 10 or 11

Not even ExcelThe reader is built in. Files from Excel, LibreOffice, PlanMaker or Collabora all open without their apps installed

Not even an internet connectionIt converts offline. You only go online to activate a license

In and out

Every common spreadsheet format in, developer-ready data out. Or skip files entirely and paste copied cells from any spreadsheet app, Google Sheets included.

Opens

XLSX
XLSM
XLSB
XLS
ODS
CSV
TSV
TXT
Pasted cells

Multi-sheet workbooks, semicolon CSVs, UTF-16, cached formula results: all handled.

Produces

JSON objects
Nested JSON
JSON-LD
NDJSON
Arrays
Headers+rows
Cell map
CSV
TSV

Pretty or compact, copied to the clipboard or saved as a file.

Shapes

customer.name
tags[0]
camelCase
snake_case
Text
Number
Boolean
Date

Nesting from headers, key transforms, and per-column type control.

What you can do

The Orders sheet with customer.name, customer.city, customer.country, items[0] and items[1] headers marked, and the preview next to it showing customer as an object with name, city and country inside it, and items as an array.

Nested

Nested JSON from your headers

Turn on Nested objects and headers like customer.name and tags[0] become real structure: objects inside objects, arrays with the blanks trimmed. The sample workbook shows it in one click.

C1 to F7 drag-selected in the Sheet2JSON grid, and the preview holding only those four columns: customer.name, customer.city, customer.country and items[0].

Selection

Select exactly what you need

Your data appears in an Excel-style grid. Export a selected range, or choose Combine worksheets into one file and check the tabs you need. Combined exports include the full used range of each checked sheet.

NDJSON

NDJSON for data pipelines

One compact object per line: the format bulk-import endpoints, log tools and streaming pipelines expect. Nested mode works here too.

JSON-LD

JSON-LD for linked data

Point it at your own context and name a default record type, and every row comes out as a node in an @graph. An @id column identifies a record, an @type column overrides the default. Context URLs are saved, never fetched.

JSON keys set to camelCase and the Column types list with order_id forced to Text, next to the preview where the key reads orderId and customer.name reads customerName.

Types & keys

Types and keys, your way

Force a column to Text so IDs keep their leading zeros, or to Number, Boolean or ISO Date. Rewrite keys to camelCase or snake_case so the output drops straight into your codebase.

Paste

Paste cells straight from a spreadsheet

No file needed. Copy a range in Excel, Google Sheets or anywhere else, press Ctrl+V, and you get the same grid, the same options and the same JSON.

Your files never leave your PC

Most converters are websites: you upload the payroll workbook and hope. Sheet2JSON is a program on your computer. There is no upload, because there is no server.

Nothing is uploadedEvery conversion runs on your computer. Not even I can see your files.
No account, no trackingInstall it and use it. The free conversions need no sign-up, and the free tier makes no network requests at all.
Works with the cable pulledConvert offline if you like. The app only goes online to validate a license key, and that request never contains your data.

What people convert for

JSON is the format your code, your API and your tools speak. The data, though, keeps arriving as spreadsheets. Sheet2JSON is the bridge, without a script and without an upload.

Seed data and fixturesReference tables, test fixtures and demo content, shaped like your models thanks to nested mode.

Config and contentProduct catalogs, translations, settings: maintained by the team in a sheet, consumed by the app as JSON.

Pipelines and importsNDJSON goes straight into bulk-import endpoints, log tooling and streaming jobs, one object per line.

"Can you send that as JSON?"When the developer asks, you answer in a minute, with the keys and types they wanted, not a mangled export.

Honest feedback from real users

★★★★★

Responsive and open to feedback

“Impressed with both the products and the support. Very responsive to questions and open to improvement suggestions. I've purchased several tools and been happy with all of them.”

John

See review

★★★★★

Fantastic support

“Had a question and got a helpful reply within hours. Really solid support. Highly recommend.”

Gary S.

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★★★★★

An awesome program and creator

“Not only does the developer respond directly to your questions, he actually acts on them. I made a feature request and it was implemented the next day. That kind of dedication is rare.”

Rob

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See all reviews →

Pay once, use it forever

Try it free on your own files. When you want more, one payment unlocks unlimited conversions. No subscription, ever.

Free

to try it on your own files

10 conversions, everything unlocked
JSON-LD, combined sheets, NDJSON, nested objects
All formats, any file size
No account, no sign-up
Updates through the Store

Frequently asked questions

Can I combine several worksheets into one JSON file?

Yes. Choose Combine worksheets into one file, check the sheets you need, and save. JSON groups each sheet under its name; NDJSON includes a sheet name and data object on each line. Each sheet keeps its own headers. Combined exports use automatic column types. This combines tabs in one workbook, not separate Excel files, and does not infer relationships between records.

Can I export JSON-LD for my AI service?

Yes. Select JSON-LD: linked data, supply the context your service expects, and optionally set a default record type. An @id column identifies records; an @type column can set a type per row. Combined worksheets become named graphs. Context URLs are included without being fetched. JSON-LD does not guarantee that an AI service accepts the file or reads every record: check its schema, graph support and upload limits. See the combined export and JSON-LD guide.

Is there a free version?

Yes. Every install includes 10 free conversions with everything unlocked, nested mode and NDJSON included, so you can try the real app on your own files before paying. Install it from the Microsoft Store and enter a license key whenever you are ready. For a quick one-off file there is also a free online converter on this site, one small file at a time.

How does nested mode work?

Name your columns the way you want the JSON shaped: customer.name and customer.city become a nested customer object, tags[0] and tags[1] become a tags array, and you can combine them as deep as you need (a.b[2].c). Ordinary headers stay ordinary flat keys, so you can mix freely. The nested mode guide walks through it.

What formats does it read and write?

In: XLSX, XLSM, XLSB, XLS, ODS, CSV, TSV and TXT, or cells pasted from any spreadsheet app, Google Sheets included. Out: JSON objects (flat or nested), JSON-LD, NDJSON, rows as arrays, headers + rows, an A1 cell map, plus CSV and TSV. Multi-sheet workbooks, semicolon CSVs and UTF-16 files all work.

Is my data private? Does it work offline?

Yes to both. Sheet2JSON runs entirely on your computer: no file is uploaded and no internet connection is needed to convert. The only request the app ever makes is validating a license key, which sends the key and a device name to my server and nothing else. On the free tier it makes no network requests at all. Details in the privacy policy.

My ID column keeps losing its leading zeros. Does this fix that?

Yes: set that column's type to Text and 007 stays "007". The same panel forces Number, Boolean (TRUE/yes/1 become real booleans) or ISO Date per column, and the coercion is deliberately lenient: a value that does not parse keeps its original value instead of silently becoming null.

Is there a file size limit?

Sheet2JSON has no fixed file-size, row or cell limit, so exports retain every loaded row. Available memory determines how large a workbook your PC can handle. The preview may shorten long output for display; Copy and Save use the full result. The free browser tool still limits input files to 5 MB.

Do I need Excel installed?

No. The spreadsheet reader is built into the app, so files from Excel, LibreOffice, OpenOffice, SoftMaker PlanMaker or Collabora Office open without any of those installed. Formula cells show their last calculated value.

Does it work on a Mac?

No. Sheet2JSON needs Windows 10 or 11. It does run inside a Windows virtual machine on a Mac (Parallels, VMware Fusion, UTM). For single files on any device, the free online converter works in the browser.

How many computers does one license cover?

A Single User license covers up to 3 of your own PCs, for example a desktop, a laptop and a work machine. The Team license covers 15 users with one key. You manage your devices yourself in your account. Need more seats? Email me.

Why not just ask ChatGPT to convert my spreadsheet?

For five rows, go ahead. For anything real it gets in the way: you upload your data to a third party, long tables get truncated or silently rewritten, numbers come back subtly wrong, and you re-do the upload for every change. Sheet2JSON is deterministic: the same file produces the same JSON every time, locally, with types you chose.

How is this better than the free web converters?

Web tools are fine for a small one-off file, which is why I run one myself. The desktop app earns its keep the moment your data is confidential (nothing is uploaded), big (no size cap), repeated (load, select, copy), or when you need shape: nested objects, NDJSON, per-column types and key transforms are things a stateless web page does not do.

What if I get stuck?

The documentation covers every option, the app's About dialog links straight to support, and you can always email sven@pythonandvba.com. I reply myself, usually within 24 hours.

Do you offer a refund?

Yes, 14 days, no questions asked. Email me at sven@pythonandvba.com.

Still have a question?

I’m Sven, the developer, and I usually reply within a day.

Get clean JSON in a minute

Nothing to configure. Drop a file, select a range, copy JSON. 10 conversions on the house.

Try Sheet2JSON for free

Sheet2JSON is an independent product by Bosau Digital LLC. It is not affiliated with or endorsed by Microsoft. Microsoft, Windows and Excel are trademarks of the Microsoft group of companies.