📦 extract-xlsx

A lightweight, zero-dependency .xlsx (Excel) file parser written in TypeScript, built as an alternative to heavier libraries like xlsx.

It reads Excel .xlsx files directly by parsing XML and returns data in structured JSON format.

✨ Features

• ✅ Reads .xlsx files (Office Open XML format)
• ✅ Dynamically detects sheets via workbook.xml
• ✅ Reads any sheet by name or defaults to the first sheet
• ✅ Parses shared strings, headers, and rows
• ✅ Works in Node.js (browser support planned)
• ✅ Minimal and blazing fast

📦 Installation

npm install extract-xlsx

or

yarn add extract-xlsx

🚀 Usage ✅ Read from file

import { readXlsxFromFile } from "extract-xlsx";

// Reads the first sheet by default
const data = await readXlsxFromFile("path/to/file.xlsx");

console.log(data);
// Output: [ { Name: "Alice", Age: "30" }, { Name: "Bob", Age: "25" } ]

✅ Read specific sheet

const data = await readXlsxFromFile("path/to/file.xlsx", "Employees");

✅ Read from buffer (custom use)

import { parseXlsx } from "extract-xlsx";
import fs from "fs";

const buffer = fs.readFileSync("sample.xlsx");
const result = await parseXlsx(buffer, "Sheet1");

✅ Sample Usage in Browser (React or Vanilla JS)

React JS

import { parseXlsx, getSheetNames } from "extract-xlsx";
import { Buffer } from "buffer"; // Need to be installed // npm install buffer
(window as any).Buffer = Buffer; // declare after installed

const Home = () => {
  const handleFileChange = async (e: React.ChangeEvent<HTMLInputElement>) => {
    const file = e.target.files?.[0];
    if (!file) return;
    const arrayBuffer = await file.arrayBuffer();
    const buffer = Buffer.from(arrayBuffer); // If you're using `buffer` polyfill in browser

    const sheetNames = await getSheetNames(buffer);
    console.log("Sheets:", sheetNames);

    const data = await parseXlsx(buffer, sheetNames[0]);
    console.log("Data:", data);
  };

  return (
    <div>
      {" "}
      <input
        id="upload"
        type="file"
        accept=".xlsx"
        onChange="{handleFileChange}"
        className="mb-4"
      />
    </div>
  );
};

export default Home;

import { parseXlsx, getSheetNames } from "extract-xlsx";
import { Buffer } from "buffer"; // Need to be installed // npm install buffer
(window as any).Buffer = Buffer; // declare after installed

document
  .querySelector("#upload")
  ?.addEventListener("change", async (e: any) => {
    const file = e.target.files[0];
    const arrayBuffer = await file.arrayBuffer();
    const buffer = Buffer.from(arrayBuffer); // If you're using `buffer` polyfill in browser

    const sheetNames = await getSheetNames(buffer);
    console.log("Sheets:", sheetNames);

    const data = await parseXlsx(buffer, sheetNames[0]);
    console.log("Data:", data);
  });

🧪 Output Format

An array of JSON objects using the first row as headers:

[
  { Name: "Alice", Age: "30" },
  { Name: "Bob", Age: "25" },
];

📄 API

readXlsxFromFile(filePath: string, sheetName?: string): Promise<any[]>
Reads from local file

sheetName (optional) — defaults to first sheet

parseXlsx(buffer: Buffer, sheetName?: string): Promise<any[]>
Accepts file Buffer

Parses .xlsx format into JSON

🔒 Limitations

Only supports .xlsx files (not .xls)

Formula and styling not supported

Returns plain data only

📚 Roadmap

Multi-sheet parser

.xls (legacy) format support

Write/Export .xlsx (optional)

🧑‍💻 Author

Created by [RAJASEKAR E C [email protected]] GitHub: rajasekar-arch