html-to-xlsx-styled

Convert an HTML <table> into a styled .xlsx workbook. Cell merges (rowspan / colspan), text content, and CSS-derived cell styles are mapped to Excel using xlsx-js-style.

Install

npm install html-to-xlsx-styled

Peer expectation: use this in environments where you can obtain a real HTMLTableElement (browser DOM, or a DOM implementation such as jsdom in Node).

Quick start (browser)

<table id="data">
  <tr><th>Name</th><th>Score</th></tr>
  <tr><td>Ada</td><td>100</td></tr>
</table>

import { exportHtmlTableToExcel } from 'html-to-xlsx-styled';

const table = document.getElementById('data');

// Get a Blob (default in browsers) and optionally trigger download
const blob = exportHtmlTableToExcel(table, {
  sheetName: 'Results',
  download: true,
  fileName: 'results.xlsx',
});

API

exportHtmlTableToExcel(table, options?)

Serializes the table to .xlsx bytes.

• Returns — By default: a Blob when Blob exists (typical browser), otherwise Uint8Array. Override with outputType.
• Options (ExportOptions):
  • sheetName — Excel sheet name (invalid characters are sanitized; max length enforced).
  • fileName — Used when download is true (default file name: export.xlsx).
  • download — If true, starts a browser download via a temporary object URL. Requires document and URL.createObjectURL; otherwise throws ExcelTableExportError with code DOM_REQUIRED. The function still returns the same binary result as when download is false.
  • useComputedStyles — When true (default), styles are taken from computed CSS. Set to false to rely on inline styles only (faster, fewer dependencies on full layout).
  • includeEmptyCellsStyles — When true, cells with no text but with visible styling may be written so formatting is preserved. Default false.
  • outputType — 'blob' | 'arrayBuffer' | 'uint8Array'. If you need bytes in Node or without Blob, use 'uint8Array' or 'arrayBuffer'.

createWorkbookFromTable(table, options?)

Builds an xlsx-js-style WorkBook from the table. Use this when you want to merge sheets, post-process cells, or write the file yourself instead of using exportHtmlTableToExcel.

import * as XLSX from 'xlsx-js-style';
import { createWorkbookFromTable } from 'html-to-xlsx-styled';

const wb = createWorkbookFromTable(table, { sheetName: 'Sheet1' });
const buf = XLSX.write(wb, { bookType: 'xlsx', type: 'array', cellStyles: true });

ExcelTableExportError

Thrown for invalid input or unsupported environment behavior. Inspect error.code:

| Code | Meaning | |-------------------|---------| | INVALID_TABLE | Value is not an HTML table element. | | DOM_REQUIRED | Operation needs a browser DOM (e.g. download: true without document / URL). | | NOT_IMPLEMENTED | Reserved. | | UNKNOWN | Other errors (e.g. unsupported outputType). |

Node / tests

Provide a HTMLTableElement from your DOM library of choice (for example jsdom):

import { JSDOM } from 'jsdom';
import { exportHtmlTableToExcel } from 'html-to-xlsx-styled';

const { window } = new JSDOM(`<table><tr><td>hi</td></tr></table>`);
const table = window.document.querySelector('table');

const bytes = exportHtmlTableToExcel(table, {
  outputType: 'uint8Array',
  useComputedStyles: false,
});

License

ISC