Universal workbench

XLSX to JSON

Create JSON from XLSX locally, with no upload or account.

Device-onlyNo uploads. Ever.

Pipelines, branches, presets, naming, and detailed controls

Display

Text sizeDensity High contrast Monospace editor

Quick start

JSON → YAML WebP → PNG SVG → React JSX Plain text → Base64

From

Help me choose the best output Suggested: CSV

What matters most?

Recommendations use the registered target format and tested fidelity classification. They never inspect or upload your content.

01Input

Drop files or a folder hereChoose XLSX files or a folder — batch input is welcome

Choose files Choose folder

or paste content

02Configure & run

XLSXJSON

structural conversion · single or batch

Conversion preflightSize, memory, engine, execution, and fidelity before you start

Input: 0 B
Estimated peak memory: 64 MiB
On-demand download: No large engine download
Execution: Responsive local worker
Fidelity: No lossy step declared

What to provideDrop one or more .xlsx workbooks. The first worksheet is exported by this route.What you’ll getProduces previewable JSON text and a correctly named download.

WorksheetEnter “first”, a 1-based sheet number, or an exact worksheet name. Available names are reported when a selection is invalid.

Output naming & batch behavior

Filename templateAvailable variables: {output} (converter’s meaningful name), {name}, {target}, {ext}, {index}. Duplicate names receive a safe numeric suffix.

Exampleoutput.json

Pipeline 1 linear · 0 branches

Why use A → B → C?

A pipeline feeds each result directly into the next compatible converter. Use one when the destination needs an intermediate representation or when you want to inspect and normalize that middle format.

JSON → CSV → XLSX turns records into rows before building a workbook.
Markdown → HTML → DOCX resolves markup before creating a document.
SVG → PNG → PDF intentionally flattens vector artwork before placing it on a page.

Only type-compatible next steps are offered. Lossy steps are marked before you run them.

1XLSX to JSONstructural

Add compatible step

Parallel output branchesEach branch receives the final linear result. Branches do not feed or depend on one another.

Add a parallel destination

Add content above to start. Nothing leaves this browser.

Processing happens locally. Your file bytes are never sent anywhere.

About this conversion

How to convert XLSX to JSON

Before you start

Drop one or more .xlsx workbooks. The first worksheet is exported by this route.

Accepted: .xlsx · application/vnd.openxmlformats-officedocument.spreadsheetml.sheet

Choose or drag one or more XLSX files onto the drop zone.
Confirm the detected format and adjust the available settings. Mixed-format batches are flagged before conversion.
Select “Convert on this device.” Produces previewable JSON text and a correctly named download.

How this converter behaves

Rows and columns are normalized through an in-memory workbook, then written as the requested table or workbook format.

What happens to your data?

The conversion engine runs in this browser tab. OmniCastConverter has no upload API and never sends your content, file name, or converted result to a server.

Fidelity and limitations

This route is classified as structural. The converter preserves meaning and structure supported by both formats.

The selected worksheet is exported; formulas use their stored values where available.