--- title: Data Import sidebar_position: 1 pagination_prev: demos/index --- import current from '/version.js'; import Tabs from '@theme/Tabs'; import TabItem from '@theme/TabItem'; import CodeBlock from '@theme/CodeBlock'; :::tip pass The ["Import Tutorial"](/docs/getting-started/examples/import) is a gentle introduction to data import and analysis. ::: ## Parsing Workbooks ### API _Extract data from spreadsheet bytes_ ```js var workbook = XLSX.read(data, opts); ``` The `read` method can extract data from spreadsheet bytes stored in a JS string, "binary string", NodeJS buffer or typed array (`Uint8Array` or `ArrayBuffer`). _Read spreadsheet bytes from a local file and extract data_ ```js var workbook = XLSX.readFile(filename, opts); ``` The `readFile` method attempts to read a spreadsheet file at the supplied path. The second `opts` argument is optional. ["Parsing Options"](/docs/api/parse-options) covers the supported properties and behaviors. :::danger pass Browsers generally do not allow reading files by specifying filename (it is a security risk), and running `XLSX.readFile` in the browser will throw an error. Deno scripts must be invoked with `--allow-read` to read from the filesystem. ::: #### Examples Here are a few common scenarios (click on each subtitle to see the code). The [demos](/docs/demos) cover special deployments in more detail. ### Example: Local File `XLSX.readFile` supports reading local files in platforms like NodeJS. In other platforms like React Native, `XLSX.read` should be called with file data. In-browser processing where users drag-and-drop files or use a file element are covered in [the "User Submissions" example.](#example-user-submissions) `readFile` uses `fs.readFileSync` under the hood: ```js var XLSX = require("xlsx"); var workbook = XLSX.readFile("test.xlsx"); ``` For Node ESM, `fs` must be loaded manually: ```js import * as fs from "fs"; import { readFile, set_fs } from "xlsx"; set_fs(fs); const workbook = readFile("test.xlsx"); ``` `readFile` can be used in the renderer process: ```js /* From the renderer process */ var XLSX = require("xlsx"); var workbook = XLSX.readFile(path); ``` Electron APIs have changed over time. The [`electron` demo](/docs/demos/desktop/electron) shows a complete example and details the required version-specific settings. [The React Native Demo](/docs/demos/mobile/reactnative#rn-file-plugins) covers tested plugins. `readFile` wraps the `File` logic in Photoshop and other ExtendScript targets. The specified path should be an absolute path: ```js #include "xlsx.extendscript.js" /* Read test.xlsx from the Documents folder */ var workbook = XLSX.readFile(Folder.myDocuments + "/test.xlsx"); ``` For user-configurable paths, `openDialog` can show a file picker: ```js #include "xlsx.extendscript.js" /* Ask user to select path */ var thisFile = File.openDialog("Select a spreadsheet"); var workbook = XLSX.readFile(thisFile.absoluteURI); ``` The [`extendscript` demo](/docs/demos/extensions/extendscript) includes complete examples for Photoshop and InDesign. `readFile` uses `Deno.readFileSync` under the hood: {`\ // @deno-types="https://cdn.sheetjs.com/xlsx-${current}/package/types/index.d.ts" import * as XLSX from 'https://cdn.sheetjs.com/xlsx-${current}/package/xlsx.mjs'; \n\ const workbook = XLSX.readFile("test.xlsx");`} :::note pass Applications reading files must be invoked with the `--allow-read` flag. ::: Bun `readFileSync` output should be wrapped in a `Buffer`: ```js import { readFileSync } from 'fs' import { read } from './xlsx.mjs' const workbook = read(Buffer.from(readFileSync(path))); ``` ### Example: User Submissions This example focuses on user-submitted files through a drag-and-drop event, HTML file input element, or network request. **For modern websites targeting Chrome 76+**, `File#arrayBuffer` is recommended: Assume `drop_dom_element` is the DOM element that will listen for changes: ```html
Drop files here
``` The event property is `e.dataTransfer`. The code snippet highlights the difference between the drag-and-drop example and the file input example: ```js // XLSX is a global from the standalone script async function handleDropAsync(e) { e.stopPropagation(); e.preventDefault(); // highlight-next-line const f = e.dataTransfer.files[0]; /* f is a File */ const data = await f.arrayBuffer(); /* data is an ArrayBuffer */ const workbook = XLSX.read(data); /* DO SOMETHING WITH workbook HERE */ } drop_dom_element.addEventListener("drop", handleDropAsync, false); ```
Starting with an HTML INPUT element with `type="file"`: ```html ``` The event property is `e.target`. The code snippet highlights the difference between the drag-and-drop example and the file input example: ```js // XLSX is a global from the standalone script async function handleFileAsync(e) { // highlight-next-line const file = e.target.files[0]; const data = await file.arrayBuffer(); /* data is an ArrayBuffer */ const workbook = XLSX.read(data); /* DO SOMETHING WITH workbook HERE */ } input_dom_element.addEventListener("change", handleFileAsync, false); ```
https://oss.sheetjs.com/sheetjs/ demonstrates the FileReader technique. **For maximal compatibility (IE10+)**, the `FileReader` approach is recommended: Assume `drop_dom_element` is the DOM element that will listen for changes: ```html
Drop files here
``` The event property is `e.dataTransfer`. The code snippet highlights the difference between the drag-and-drop example and the file input example: ```js function handleDrop(e) { e.stopPropagation(); e.preventDefault(); // highlight-next-line var f = e.dataTransfer.files[0]; /* f is a File */ var reader = new FileReader(); reader.onload = function(e) { var data = e.target.result; /* reader.readAsArrayBuffer(file) -> data will be an ArrayBuffer */ var workbook = XLSX.read(data); /* DO SOMETHING WITH workbook HERE */ }; reader.readAsArrayBuffer(f); } drop_dom_element.addEventListener("drop", handleDrop, false); ```
Starting with an HTML INPUT element with `type="file"`: ```html ``` The event property is `e.target`. The code snippet highlights the difference between the drag-and-drop example and the file input example: ```js function handleFile(e) { // highlight-next-line var file = e.target.files[0]; var reader = new FileReader(); reader.onload = function(e) { var data = e.target.result; /* reader.readAsArrayBuffer(file) -> data will be an ArrayBuffer */ var workbook = XLSX.read(e.target.result); /* DO SOMETHING WITH workbook HERE */ }; reader.readAsArrayBuffer(file); } input_dom_element.addEventListener("change", handleFile, false); ```
The [`oldie` demo](/docs/demos/frontend/legacy#internet-explorer) shows an IE-compatible fallback scenario.
`read` can accept a NodeJS buffer. `readFile` can read files generated by a HTTP POST request body parser like **`formidable`**: ```js const XLSX = require("xlsx"); const http = require("http"); const formidable = require("formidable"); const server = http.createServer((req, res) => { const form = new formidable.IncomingForm(); form.parse(req, (err, fields, files) => { /* grab the first file */ const f = Object.entries(files)[0][1]; const path = f.filepath; const workbook = XLSX.readFile(path); /* DO SOMETHING WITH workbook HERE */ }); }).listen(process.env.PORT || 7262); ``` The [`server` demo](/docs/demos/net/server) includes more advanced examples. Drash is a HTTP server framework for Deno. In a `POST` request handler, the body parser can pull file data into a `Uint8Array`: {`\ // @deno-types="https://cdn.sheetjs.com/xlsx-${current}/package/types/index.d.ts" import * as XLSX from 'https://cdn.sheetjs.com/xlsx-${current}/package/xlsx.mjs'; /* load the codepage support library for extended support with older formats */ import * as cptable from 'https://cdn.sheetjs.com/xlsx-${current}/package/dist/cpexcel.full.mjs'; XLSX.set_cptable(cptable); \n\ import * as Drash from "https://cdn.jsdelivr.net/gh/drashland/drash@v2.8.1/mod.ts"; \n\ class SheetResource extends Drash.Resource { public paths = ["/"]; \n\ public POST(request: Drash.Request, response: Drash.Response) { // highlight-next-line const file = request.bodyParam("file"); if (!file) throw new Error("File is required!"); // highlight-next-line var wb = XLSX.read(file.content); var html = XLSX.utils.sheet_to_html(wb.Sheets[wb.SheetNames[0]]); return response.html(html); } } \n\ const server = new Drash.Server({ hostname: "", port: 7262, protocol: "http", resources: [ // highlight-next-line SheetResource, ], }); \n\ server.run();`} :::note pass Deno must be run with the `--allow-net` flag to enable network requests: ```bash deno run --allow-net test-server.ts ``` To test, submit a POST request to `http://localhost:7262` with an attachment: ```bash curl -X POST -F "file=@test.xlsx" http://localhost:7262/ ``` :::
### Example: Remote File This example focuses on fetching files ("Ajax" in browser parlance) using APIs like `XMLHttpRequest` and `fetch` as well as third-party libraries. For modern websites targeting Chrome 42+, `fetch` is recommended: ```js // XLSX is a global from the standalone script (async() => { const url = "https://sheetjs.com/pres.xlsx"; const data = await (await fetch(url)).arrayBuffer(); /* data is an ArrayBuffer */ const workbook = XLSX.read(data); /* DO SOMETHING WITH workbook HERE */ })(); ``` For broader support, the `XMLHttpRequest` approach is recommended: ```js var url = "https://sheetjs.com/pres.xlsx"; /* set up async GET request */ var req = new XMLHttpRequest(); req.open("GET", url, true); req.responseType = "arraybuffer"; req.onload = function(e) { var workbook = XLSX.read(req.response); /* DO SOMETHING WITH workbook HERE */ }; req.send(); ``` The [HTTP Downloads demo](/docs/demos/net/network) includes examples using browser APIs and wrapper libraries. https://oss.sheetjs.com/sheetjs/ajax.html shows fallback approaches for IE6+. NodeJS releases starting from version 18.0 have native support for fetch: ```js const XLSX = require("xlsx"); const url = "https://sheetjs.com/pres.xlsx"; const data = await (await fetch(url)).arrayBuffer(); /* data is an ArrayBuffer */ const workbook = XLSX.read(data); ``` For broader compatibility, third-party modules are recommended. **`request`** requires a `null` encoding to yield Buffers: ```js var XLSX = require("xlsx"); var request = require("request"); var url = "https://sheetjs.com/pres.xlsx"; request({url: url, encoding: null}, function(err, resp, body) { var workbook = XLSX.read(body); /* DO SOMETHING WITH workbook HERE */ }); ``` **`axios`** works the same way in browser and in NodeJS: ```js const XLSX = require("xlsx"); const axios = require("axios"); const url = "https://sheetjs.com/pres.xlsx"; (async() => { const res = await axios.get(url, {responseType: "arraybuffer"}); /* res.data is a Buffer */ const workbook = XLSX.read(res.data); /* DO SOMETHING WITH workbook HERE */ })(); ``` Bun has native support for `fetch`. Using the [NodeJS package](/docs/getting-started/installation/nodejs): ```js import * as XLSX from 'xlsx'; /* load the codepage support library for extended support with older formats */ import * as cptable from 'xlsx/dist/cpexcel.full.mjs'; XLSX.set_cptable(cptable); const url = "https://sheetjs.com/pres.xlsx"; // highlight-next-line const data = await (await fetch(url)).arrayBuffer(); /* data is an ArrayBuffer */ const workbook = XLSX.read(data); ``` Deno has native support for `fetch`. {`\ // @deno-types="https://cdn.sheetjs.com/xlsx-${current}/package/types/index.d.ts" import * as XLSX from 'https://cdn.sheetjs.com/xlsx-${current}/package/xlsx.mjs'; /* load the codepage support library for extended support with older formats */ import * as cptable from 'https://cdn.sheetjs.com/xlsx-${current}/package/dist/cpexcel.full.mjs'; XLSX.set_cptable(cptable); \n\ const url = "https://sheetjs.com/pres.xlsx"; // highlight-next-line const data = await (await fetch(url)).arrayBuffer(); /* data is an ArrayBuffer */ const workbook = XLSX.read(data);`} :::note pass Deno must be run with the `--allow-net` flag to enable network requests: ```bash deno run --allow-net test-fetch.ts ``` ::: The `net` module in the main process can make HTTP/HTTPS requests to external resources. Responses should be manually concatenated using `Buffer.concat`: ```js const XLSX = require("xlsx"); const { net } = require("electron"); const url = "https://sheetjs.com/pres.xlsx"; const req = net.request(url); req.on("response", (res) => { const bufs = []; // this array will collect all of the buffers res.on("data", (chunk) => { bufs.push(chunk); }); res.on("end", () => { const workbook = XLSX.read(Buffer.concat(bufs)); /* DO SOMETHING WITH workbook HERE */ }); }); req.end(); ``` ### Example: Readable Streams :::caution pass The recommended approach is to buffer streams in memory and process once all of the data has been collected. A proper streaming parse is technically impossible.
Technical details (click to show) XLSX, XLSB, NUMBERS, and ODS files are ultimately ZIP files that contain binary and XML entries. The ZIP file format stores the table of contents ("end of central directory" record) at the end of the file, so a proper parse of a ZIP file requires scanning from the end. Streams do not provide random access into the data, so the only correct approach involves buffering the entire stream. XLS, XLR, QPW, and Works 4 for Mac files use the "Compound File Binary Format". It is a container format that can hold multiple "files" and "folders". It also has a table of contents ("directory sectors") but these can be placed anywhere in the file! The only correct approach involves buffering enough of the stream to find the full table of contents, but the added complexity has little benefit when testing against real-world files generated by various versions of Excel and other tools.
::: When dealing with `ReadableStream`, the easiest approach is to buffer the stream and process the whole thing at the end: ```js // XLSX is a global from the standalone script async function buffer_RS(stream) { /* collect data */ const buffers = []; const reader = stream.getReader(); for(;;) { const res = await reader.read(); if(res.value) buffers.push(res.value); if(res.done) break; } /* concat */ const out = new Uint8Array(buffers.reduce((acc, v) => acc + v.length, 0)); let off = 0; for(const u8 of buffers) { out.set(u8, off); off += u8.length; } return out; } const data = await buffer_RS(stream); /* data is Uint8Array */ const workbook = XLSX.read(data); ``` When dealing with Readable Streams, the easiest approach is to buffer the stream and process the whole thing at the end: ```js var XLSX = require("xlsx"); function process_RS(stream, cb) { var buffers = []; stream.on("data", function(data) { buffers.push(data); }); stream.on("end", function() { var buffer = Buffer.concat(buffers); var workbook = XLSX.read(buffer); /* DO SOMETHING WITH workbook IN THE CALLBACK */ cb(workbook); }); } ``` In recent versions of NodeJS, Promises are preferred: ```js var XLSX = require("xlsx"); /* async_RS reads a stream and returns a Promise resolving to a workbook */ const async_RS = (stream) => new Promise((res, rej) => { var buffers = []; stream.on("data", function(data) { buffers.push(data); }); stream.on("end", function() { const buf = Buffer.concat(buffers); const wb = XLSX.read(buf); res(wb); }); }); ``` In addition to the browser `ReadableStream` API, Deno has a `Reader` class. For these streams, `std` provides a `readAll` method to collect data into a `Uint8Array`. This example reads from a file using `Deno.open` and prints the worksheet names array: {`\ // @deno-types="https://cdn.sheetjs.com/xlsx-${current}/package/types/index.d.ts" import * as XLSX from 'https://cdn.sheetjs.com/xlsx-${current}/package/xlsx.mjs'; \n\ import { readAll } from "https://deno.land/std/streams/conversion.ts"; \n\ /* Simple Deno.Reader from a file */ const file = await Deno.open("test.xlsx", {read: true}); \n\ /* \`content\` will be a Uint8Array holding the full contents of the stream */ const content = await readAll(file); \n\ /* Since this is a Uint8Array, \`XLSX.read\` "just works" */ const wb = XLSX.read(content); console.log(wb.SheetNames);`} More detailed examples are covered in the [included demos](/docs/demos/) ## Processing JSON and JS Data JSON and JS data tend to represent single worksheets. This section will use a few utility functions to generate workbooks. _Create a new Workbook_ ```js var workbook = XLSX.utils.book_new(); ``` The [`book_new` utility function](/docs/api/utilities/wb) creates an empty workbook with no worksheets. #### API _Create a worksheet from an array of arrays of JS values_ ```js var worksheet = XLSX.utils.aoa_to_sheet(aoa, opts); ``` The `aoa_to_sheet` utility function walks an "array of arrays" in row-major order, generating a worksheet object. The following snippet generates a sheet with cell `A1` set to the string `A1`, cell `B1` set to `B1`, etc: ```js var worksheet = XLSX.utils.aoa_to_sheet([ ["A1", "B1", "C1"], ["A2", "B2", "C2"], ["A3", "B3", "C3"] ]); ``` ["Array of Arrays Input"](/docs/api/utilities/array#array-of-arrays-input) describes the function and the optional `opts` argument in more detail. _Create a worksheet from an array of JS objects_ ```js var worksheet = XLSX.utils.json_to_sheet(jsa, opts); ``` The `json_to_sheet` utility function walks an array of JS objects in order, generating a worksheet object. By default, it will generate a header row and one row per object in the array. The optional `opts` argument has settings to control the column order and header output. ["Array of Objects Input"](/docs/api/utilities/array#array-of-objects-input) describes the function and the optional `opts` argument in more detail. #### Examples ["Export Tutorial"](/docs/getting-started/examples/export) contains a detailed example of fetching data from a JSON Endpoint and generating a workbook. [`x-spreadsheet`](/docs/demos/grid/xs) is an interactive data grid for previewing and modifying structured data in the web browser. ["TensorFlow.js"](/docs/demos/math/tensorflow) covers strategies for creating worksheets from ML library exports (datasets stored in Typed Arrays).
Records from a database query (SQL or no-SQL) (click to show) The [`data` demo](/docs/demos/data/) includes examples of working with databases and query results.
## Processing HTML Tables #### API _Create a worksheet by scraping an HTML TABLE in the page_ ```js var worksheet = XLSX.utils.table_to_sheet(dom_element, opts); ``` The `table_to_sheet` utility function takes a DOM TABLE element and iterates through the rows to generate a worksheet. The `opts` argument is optional. ["HTML Table Input"](/docs/api/utilities/html#html-table-input) describes the function in more detail. _Create a workbook by scraping an HTML TABLE in the page_ ```js var workbook = XLSX.utils.table_to_book(dom_element, opts); ``` The `table_to_book` utility function follows the same logic as `table_to_sheet`. After generating a worksheet, it creates a blank workbook and appends the spreadsheet. The options argument supports the same options as `table_to_sheet`, with the addition of a `sheet` property to control the worksheet name. If the property is missing or no options are specified, the default name `Sheet1` is used. #### Examples The [Headless Demo](/docs/demos/net/headless) includes examples of server-side spreadsheet generation from HTML TABLE elements using headless Chromium ("Puppeteer") and other browsers ("Playwright") Here are a few common scenarios (click on each subtitle to see the code):
HTML TABLE element in a webpage (click to show) {`\ \n\
SheetJS
1234567
\n\ `}
Multiple tables on a web page can be converted to individual worksheets: ```js /* create new workbook */ var workbook = XLSX.utils.book_new(); /* convert table "table1" to worksheet named "Sheet1" */ var sheet1 = XLSX.utils.table_to_sheet(document.getElementById("table1")); XLSX.utils.book_append_sheet(workbook, sheet1, "Sheet1"); /* convert table "table2" to worksheet named "Sheet2" */ var sheet2 = XLSX.utils.table_to_sheet(document.getElementById("table2")); XLSX.utils.book_append_sheet(workbook, sheet2, "Sheet2"); /* workbook now has 2 worksheets */ ``` Alternatively, the HTML code can be extracted and parsed: ```js var htmlstr = document.getElementById("tableau").outerHTML; var workbook = XLSX.read(htmlstr, {type:"string"}); ```
Chrome/Chromium Extension (click to show) The ["Chrome and Chromium" demo](/docs/demos/extensions/chromium/) includes a complete example and enumerates the required permissions and other settings. In an extension, it is recommended to generate the workbook in a content script and pass the object back to the extension: ```js /* in the worker script */ chrome.runtime.onMessage.addListener(function(msg, sender, cb) { /* pass a message like { sheetjs: true } from the extension to scrape */ if(!msg || !msg.sheetjs) return; /* create a new workbook */ var workbook = XLSX.utils.book_new(); /* loop through each table element */ var tables = document.getElementsByTagName("table") for(var i = 0; i < tables.length; ++i) { var worksheet = XLSX.utils.table_to_sheet(tables[i]); XLSX.utils.book_append_sheet(workbook, worksheet, "Table" + i); } /* pass back to the extension */ return cb(workbook); }); ```
NodeJS HTML Tables without a browser (click to show) NodeJS does not include a DOM implementation and Puppeteer requires a hefty Chromium build. The ["Synthetic DOM"](/docs/demos/net/dom) demo includes examples for NodeJS.