SheetJS alternative for ODF spreadsheets

Why look for a SheetJS alternative?

SheetJS (xlsx) is the most widely used JavaScript spreadsheet library. It supports many formats and is well-maintained. However, several factors lead developers to look for alternatives:

• Licensing — SheetJS Pro features require a paid license. The free Community Edition has restrictions on commercial use for some features.
• ODF focus — If your target format is .ods (OpenDocument Spreadsheet), odf-kit is purpose-built for ODF and produces spec-compliant output validated on every CI run.
• Bundle size — SheetJS includes support for many legacy formats. odf-kit/ods is focused on ODF only, with zero transitive dependencies.
• Government and public sector — Many governments mandate ODF (ISO/IEC 26300). odf-kit targets this use case directly.

Install

Generate ODS spreadsheets

Use OdsDocument from odf-kit to create .ods files from scratch — the equivalent of SheetJS's XLSX.utils.book_new() workflow, but for ODF:

import { OdsDocument } from "odf-kit";
import { writeFileSync } from "fs";

const doc = new OdsDocument();
const sheet = doc.addSheet("Sales");

// Auto-typed cells: number, Date, boolean, string, null
sheet.addRow(["Month", "Revenue", "Growth"], { bold: true, backgroundColor: "#DDDDDD" });
sheet.addRow(["January",  12500, 0.08]);
sheet.addRow(["February", 14200, 0.136]);
sheet.addRow(["Total", { value: "=SUM(B2:B3)", type: "formula" }]);

// Number formats
sheet.addRow([{ value: 1234.56, type: "currency", numberFormat: "currency:EUR" }]);
sheet.addRow([{ value: 0.1234, type: "percentage", numberFormat: "percentage:1" }]);

// Merged cells, freeze, column width, tab color
sheet.addRow([{ value: "Q1 Summary", type: "string", colSpan: 3, bold: true }]);
sheet.setColumnWidth(0, "4cm");
sheet.freezeRows(1);
sheet.setTabColor("#4CAF50");

const bytes = await doc.save();
writeFileSync("sales.ods", bytes);

Convert XLSX to ODS

Use xlsxToOds from odf-kit/xlsx to convert .xlsx files to .ods — no SheetJS dependency, no extra install:

import { xlsxToOds } from "odf-kit/xlsx";
import { readFileSync, writeFileSync } from "fs";

const ods = await xlsxToOds(readFileSync("report.xlsx"));
writeFileSync("report.ods", ods);

// Also works in the browser
const ods2 = await xlsxToOds(await file.arrayBuffer());

Preserves: strings, numbers, booleans, dates (Excel serial → Date), formulas (cached result), merged cells (colSpan/rowSpan), freeze panes, multiple sheets. Own XLSX parser — no SheetJS, no transitive dependencies.

Read ODS files

Use readOds from odf-kit/ods-reader to parse .ods files into typed JavaScript values — the equivalent of SheetJS's XLSX.read() + utils.sheet_to_json():

import { readOds, odsToHtml } from "odf-kit/ods-reader";
import { readFileSync } from "fs";

const model = readOds(readFileSync("data.ods"));

for (const row of model.sheets[0].rows) {
  for (const cell of row.cells) {
    console.log(cell.type, cell.value);
    // type: "string"|"float"|"boolean"|"date"|"formula"|"empty"|"covered"
    // value: string|number|boolean|Date|null — never a display string
  }
}

// Or convert to an HTML table directly
const html = odsToHtml(readFileSync("data.ods"));

Comparison

When to use odf-kit vs SheetJS

Use odf-kit when:

• Your target format is .ods (OpenDocument Spreadsheet)
• You need ODF compliance for government or public sector requirements
• You want zero transitive dependencies and Apache 2.0 licensing with no ambiguity
• You also need ODT document generation in the same project

Use SheetJS when:

• You need to read or write legacy formats (.xls, .xlsb, .xlsm with macros)
• You need to write .xlsx output specifically
• You need advanced Excel-specific features (pivot tables, charts, conditional formatting)