Convert XLSX to JSON

Read an .xlsx file and get a JSON document back — without uploading anything. ReoGrid parses the file in the browser, then toJson() serializes the full workbook (all sheets, styles, formulas) to a lossless ReoGrid JSON document.

Full example

import { createReogrid } from '@reogrid/pro';

const grid = createReogrid('#grid', { licenseKey: 'YOUR-LICENSE-KEY' });

const input = document.querySelector<HTMLInputElement>('#file')!;
input.addEventListener('change', async (e) => {
  const file = (e.target as HTMLInputElement).files?.[0];
  if (!file) return;

  await grid.loadFromFile(file);   // parse + render the .xlsx
  const doc = grid.toJson();       // whole workbook → ReoGrid JSON

  const json = JSON.stringify(doc, null, 2);
  console.log(json);
  // ...copy to clipboard, download, or POST to your API
});

<input type="file" accept=".xlsx" id="file" />
<div id="grid" style="width: 100%; height: 400px;"></div>

Download the JSON

function downloadJson(doc: unknown, filename = 'workbook.json') {
  const blob = new Blob([JSON.stringify(doc, null, 2)], { type: 'application/json' });
  const url = URL.createObjectURL(blob);
  const a = Object.assign(document.createElement('a'), { href: url, download: filename });
  a.click();
  URL.revokeObjectURL(url);
}

await grid.loadFromFile(file);
downloadJson(grid.toJson(), file.name.replace(/\.xlsx$/i, '.json'));

Single sheet only

To serialize just the active worksheet (not the whole workbook), use the worksheet-level writer:

import { stringifyReoGridJson } from '@reogrid/pro';

await grid.loadFromFile(file);
const json = stringifyReoGridJson(grid.worksheet, { pretty: true });

Restore it later

const saved = localStorage.getItem('workbook');
if (saved) grid.loadJson(JSON.parse(saved));

Notes

Lossless. ReoGrid JSON keeps everything xlsx round-trips plus ReoGrid-only features (custom cell types, all conditional-format rules). It is the format to use for save/restore.
Need plain rows of data ([{ name, price }, …]) instead of the full document? See Convert XLSX to data rows.
Lite vs Pro. xlsx import works in Lite too, but Lite truncates files past 100 rows × 26 columns. Convert real-world files with Pro.
Everything runs client-side — the file never leaves the browser.