xlsx

Parser and writer for various spreadsheet formats. Pure-JS cleanroom implementation from official specifications, related documents, and test files. Emphasis on parsing and writing robustness, cross-format feature compatibility with a unified JS representation, and ES3/ES5 browser compatibility back to IE6.

In-Browser Demo

Source Code

Commercial Support

File format support for known spreadsheet data formats:

Table of Contents

• Installation
  • JS Ecosystem Demos
  • Optional Modules
  • ECMAScript 5 Compatibility
• Parsing Workbooks
• Working with the Workbook
• Writing Workbooks
• Interface
  • Parsing functions
  • Writing functions
  • Utilities
• Workbook / Worksheet / Cell Object Description
  • General Structures
  • Cell Object
  • Data Types
  • Formulae
  • Worksheet Object
  • Workbook Object
• Parsing Options
  • Input Type
  • Guessing File Type
• Writing Options
  • Supported Output Formats
  • Output Type
• Utility Functions
  • Formulae Output
  • CSV and general DSV Output
  • JSON
• File Formats
  • Excel 2007+ XML (XLSX/XLSM)
  • Excel 2.0-95 (BIFF2/BIFF3/BIFF4/BIFF5)
  • Excel 97-2004 Binary (BIFF8)
  • Excel 2003-2004 (SpreadsheetML)
  • Excel 2007+ Binary (XLSB, BIFF12)
  • OpenDocument Spreadsheet (ODS/FODS) and Uniform Office Spreadsheet (UOS1/2)
  • Comma-Separated Values
  • HTML
• Testing
  • Tested Environments
  • Test Files
• Contributing
• License
• References
• Badges

Installation

With npm:

$ npm install xlsx

In the browser:

<script lang="javascript" src="dist/xlsx.core.min.js"></script>

With bower:

$ bower install js-xlsx

CDNjs automatically pulls the latest version and makes all versions available at http://cdnjs.com/libraries/xlsx

JS Ecosystem Demos

The demos directory includes sample projects for:

• browserify
• requirejs
• webpack

Optional Modules

The node version automatically requires modules for additional features. Some of these modules are rather large in size and are only needed in special circumstances, so they do not ship with the core. For browser use, they must be included directly:

<!-- international support from js-codepage -->
<script src="dist/cpexcel.js"></script>

An appropriate version for each dependency is included in the dist/ directory.

The complete single-file version is generated at dist/xlsx.full.min.js

Webpack and browserify builds include optional modules by default. Webpack can be configured to remove support with resolve.alias:

  /* uncomment the lines below to remove support */
  resolve: {
    alias: { "./dist/cpexcel.js": "" } // <-- omit international support
  }

ECMAScript 5 Compatibility

Since xlsx.js uses ES5 functions like Array#forEach, older browsers require Polyfills. This repo and the gh-pages branch include a shim

To use the shim, add the shim before the script tag that loads xlsx.js:

<script type="text/javascript" src="/path/to/shim.js"></script>

Parsing Workbooks

For parsing, the first step is to read the file. This involves acquiring the data and feeding it into the library. Here are a few common scenarios:

• node readFile:

if(typeof require !== 'undefined') XLSX = require('xlsx');
var workbook = XLSX.readFile('test.xlsx');
/* DO SOMETHING WITH workbook HERE */

• ajax (for a more complete example that works in older browsers, check the demo at http://oss.sheetjs.com/js-xlsx/ajax.html):

/* set up XMLHttpRequest */
var url = "test_files/formula_stress_test_ajax.xlsx";
var oReq = new XMLHttpRequest();
oReq.open("GET", url, true);
oReq.responseType = "arraybuffer";

oReq.onload = function(e) {
  var arraybuffer = oReq.response;

  /* convert data to binary string */
  var data = new Uint8Array(arraybuffer);
  var arr = new Array();
  for(var i = 0; i != data.length; ++i) arr[i] = String.fromCharCode(data[i]);
  var bstr = arr.join("");

  /* Call XLSX */
  var workbook = XLSX.read(bstr, {type:"binary"});

  /* DO SOMETHING WITH workbook HERE */
}

oReq.send();

• HTML5 drag-and-drop using readAsBinaryString or readAsArrayBuffer: note: readAsBinaryString and readAsArrayBuffer may not be available in every browser. Use dynamic feature tests to determine which method to use.

/* processing array buffers, only required for readAsArrayBuffer */
function fixdata(data) {
  var o = "", l = 0, w = 10240;
  for(; l<data.byteLength/w; ++l) o+=String.fromCharCode.apply(null,new Uint8Array(data.slice(l*w,l*w+w)));
  o+=String.fromCharCode.apply(null, new Uint8Array(data.slice(l*w)));
  return o;
}

var rABS = true; // true: readAsBinaryString ; false: readAsArrayBuffer
/* set up drag-and-drop event */
function handleDrop(e) {
  e.stopPropagation();
  e.preventDefault();
  var files = e.dataTransfer.files;
  var i,f;
  for (i = 0; i != files.length; ++i) {
    f = files[i];
    var reader = new FileReader();
    var name = f.name;
    reader.onload = function(e) {
      var data = e.target.result;

      var workbook;
      if(rABS) {
        /* if binary string, read with type 'binary' */
        workbook = XLSX.read(data, {type: 'binary'});
      } else {
        /* if array buffer, convert to base64 */
        var arr = fixdata(data);
        workbook = XLSX.read(btoa(arr), {type: 'base64'});
      }

      /* DO SOMETHING WITH workbook HERE */
    };
    if(rABS) reader.readAsBinaryString(f);
    else reader.readAsArrayBuffer(f);
  }
}
drop_dom_element.addEventListener('drop', handleDrop, false);

• HTML5 input file element using readAsBinaryString or readAsArrayBuffer:

/* fixdata and rABS are defined in the drag and drop example */
function handleFile(e) {
  var files = e.target.files;
  var i,f;
  for (i = 0; i != files.length; ++i) {
    f = files[i];
    var reader = new FileReader();
    var name = f.name;
    reader.onload = function(e) {
      var data = e.target.result;

      var workbook;
      if(rABS) {
        /* if binary string, read with type 'binary' */
        workbook = XLSX.read(data, {type: 'binary'});
      } else {
        /* if array buffer, convert to base64 */
        var arr = fixdata(data);
        workbook = XLSX.read(btoa(arr), {type: 'base64'});
      }

      /* DO SOMETHING WITH workbook HERE */
    };
    reader.readAsBinaryString(f);
  }
}
input_dom_element.addEventListener('change', handleFile, false);

Working with the Workbook

The full object format is described later in this README.

This example extracts the value stored in cell A1 from the first worksheet:

var first_sheet_name = workbook.SheetNames[0];
var address_of_cell = 'A1';

/* Get worksheet */
var worksheet = workbook.Sheets[first_sheet_name];

/* Find desired cell */
var desired_cell = worksheet[address_of_cell];

/* Get the value */
var desired_value = (desired_cell ? desired_cell.v : undefined);

Complete examples:

• http://oss.sheetjs.com/js-xlsx/ HTML5 File API / Base64 Text / Web Workers

Note that older versions of IE do not support HTML5 File API, so the base64 mode is used for testing. On OSX you can get the base64 encoding with:

$ <target_file base64 | pbcopy

On Windows XP and up you can get the base64 encoding using certutil:

> certutil -encode target_file target_file.b64

(note: You have to open the file and remove the header and footer lines)

• http://oss.sheetjs.com/js-xlsx/ajax.html XMLHttpRequest

• https://github.com/SheetJS/js-xlsx/blob/master/bin/xlsx.njs node

The node version installs a command line tool xlsx which can read spreadsheet files and output the contents in various formats. The source is available at xlsx.njs in the bin directory.

Some helper functions in XLSX.utils generate different views of the sheets:

• XLSX.utils.sheet_to_csv generates CSV
• XLSX.utils.sheet_to_json generates an array of objects
• XLSX.utils.sheet_to_formulae generates a list of formulae

Writing Workbooks

For writing, the first step is to generate output data. The helper functions write and writeFile will produce the data in various formats suitable for dissemination. The second step is to actual share the data with the end point. Assuming workbook is a workbook object:

• nodejs write to file:

/* output format determined by filename */
XLSX.writeFile(workbook, 'out.xlsx');
/* at this point, out.xlsx is a file that you can distribute */

• browser generate binary blob and "download" to client (using FileSaver.js for download):

/* bookType can be 'xlsx' or 'xlsm' or 'xlsb' or 'ods' */
var wopts = { bookType:'xlsx', bookSST:false, type:'binary' };

var wbout = XLSX.write(workbook,wopts);

function s2ab(s) {
  var buf = new ArrayBuffer(s.length);
  var view = new Uint8Array(buf);
  for (var i=0; i!=s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF;
  return buf;
}

/* the saveAs call downloads a file on the local machine */
saveAs(new Blob([s2ab(wbout)],{type:"application/octet-stream"}), "test.xlsx");

Complete examples:

• http://sheetjs.com/demos/writexlsx.html generates a simple file
• http://git.io/WEK88Q writing an array of arrays in nodejs
• http://sheetjs.com/demos/table.html exporting an HTML table

Interface

XLSX is the exposed variable in the browser and the exported node variable

XLSX.version is the version of the library (added by the build script).

XLSX.SSF is an embedded version of the format library.

Parsing functions

XLSX.read(data, read_opts) attempts to parse data.

XLSX.readFile(filename, read_opts) attempts to read filename and parse.

Parse options are described in the Parsing Options section.

Writing functions

XLSX.write(wb, write_opts) attempts to write the workbook wb

XLSX.writeFile(wb, filename, write_opts) attempts to write wb to filename

Write options are described in the Writing Options section.

Utilities

Utilities are available in the XLSX.utils object:

Exporting:

• sheet_to_json converts a worksheet object to an array of JSON objects. sheet_to_row_object_array is an alias that will be removed in the future.
• sheet_to_csv generates delimiter-separated-values output.
• sheet_to_formulae generates a list of the formulae (with value fallbacks).

Exporters are described in the Utility Functions section.

Cell and cell address manipulation:

• format_cell generates the text value for a cell (using number formats)
• {en,de}code_{row,col} convert between 0-indexed rows/cols and A1 forms.
• {en,de}code_cell converts cell addresses
• {en,de}code_range converts cell ranges

Workbook / Worksheet / Cell Object Description

js-xlsx conforms to the Common Spreadsheet Format (CSF):

General Structures

Cell address objects are stored as {c:C, r:R} where C and R are 0-indexed column and row numbers, respectively. For example, the cell address B5 is represented by the object {c:1, r:4}.

Cell range objects are stored as {s:S, e:E} where S is the first cell and E is the last cell in the range. The ranges are inclusive. For example, the range A3:B7 is represented by the object {s:{c:0, r:2}, e:{c:1, r:6}}. Utils use the following pattern to walk each of the cells in a range:

for(var R = range.s.r; R <= range.e.r; ++R) {
  for(var C = range.s.c; C <= range.e.c; ++C) {
    var cell_address = {c:C, r:R};
  }
}

Cell Object

Key	Description
v	raw value (see Data Types section for more info)
w	formatted text (if applicable)
t	cell type: b Boolean, n Number, e error, s String, d Date
f	cell formula encoded as an A1-style string (if applicable)
F	range of enclosing array if formula is array formula (if applicable)
r	rich text encoding (if applicable)
h	HTML rendering of the rich text (if applicable)
c	comments associated with the cell
z	number format string associated with the cell (if requested)
l	cell hyperlink object (.Target holds link, .tooltip is tooltip)
s	the style/theme of the cell (if applicable)

Built-in export utilities (such as the CSV exporter) will use the w text if it is available. To change a value, be sure to delete cell.w (or set it to undefined) before attempting to export. The utilities will regenerate the w text from the number format (cell.z) and the raw value if possible.

The actual array formula is stored in the f field of the first cell in the array range. Other cells in the range will omit the f field.

Data Types

The raw value is stored in the v field, interpreted based on the t field.

Type b is the Boolean type. v is interpreted according to JS truth tables.

Type e is the Error type. v holds the number and w holds the common name:

Value	Error Meaning
0x00	#NULL!
0x07	#DIV/0!
0x0F	#VALUE!
0x17	#REF!
0x1D	#NAME?
0x24	#NUM!
0x2A	#N/A
0x2B	#GETTING_DATA

Type n is the Number type. This includes all forms of data that Excel stores as numbers, such as dates/times and Boolean fields. Excel exclusively uses data that can be fit in an IEEE754 floating point number, just like JS Number, so the v field holds the raw number. The w field holds formatted text.

Type d is the Date type, generated only when the option cellDates is passed. Since JSON does not have a natural Date type, parsers are generally expected to store ISO 8601 Date strings like you would get from date.toISOString(). On the other hand, writers and exporters should be able to handle date strings and JS Date objects. Note that Excel disregards timezone modifiers and treats all dates in the local timezone. js-xlsx does not correct for this error.

Type s is the String type. v should be explicitly stored as a string to avoid possible confusion.

Formulae

The A1-style formula string is stored in the f field. Even though different file formats store the formulae in different ways, the formats are converted.

Shared formulae are decompressed and each cell has the correct formula.

Array formulae are stored in the top-left cell of the array block. All cells of an array formula have a F field corresponding to the range. A single-cell formula can be distinguished from a plain formula by the presence of F field.

The sheet_to_formulae method generates one line per formula or array formula. Array formulae are rendered in the form range=formula while plain cells are rendered in the form cell=formula or value.

Worksheet Object

Each key that does not start with ! maps to a cell (using A-1 notation)

worksheet[address] returns the cell object for the specified address.

Special worksheet keys (accessible as worksheet[key], each starting with !):

• ws['!ref']: A-1 based range representing the worksheet range. Functions that work with sheets should use this parameter to determine the range. Cells that are assigned outside of the range are not processed. In particular, when writing a worksheet by hand, be sure to update the range. For a longer discussion, see http://git.io/KIaNKQ

  Functions that handle worksheets should test for the presence of !ref field. If the !ref is omitted or is not a valid range, functions are free to treat the sheet as empty or attempt to guess the range. The standard utilities that ship with this library treat sheets as empty (for example, the CSV output is empty string).

  When reading a worksheet with the sheetRows property set, the ref parameter will use the restricted range. The original range is set at ws['!fullref']

• ws['!cols']: array of column properties objects. Column widths are actually stored in files in a normalized manner, measured in terms of the "Maximum Digit Width" (the largest width of the rendered digits 0-9, in pixels). When parsed, the column objects store the pixel width in the wpx field, character width in the wch field, and the maximum digit width in the MDW field.

• ws['!merges']: array of range objects corresponding to the merged cells in the worksheet. Plaintext utilities are unaware of merge cells. CSV export will write all cells in the merge range if they exist, so be sure that only the first cell (upper-left) in the range is set.

Workbook Object

workbook.SheetNames is an ordered list of the sheets in the workbook

wb.Sheets[sheetname] returns an object representing the worksheet.

wb.Props is an object storing the standard properties. wb.Custprops stores custom properties. Since the XLS standard properties deviate from the XLSX standard, XLS parsing stores core properties in both places. .

Parsing Options

The exported read and readFile functions accept an options argument:

Option Name	Default	Description
type		Input data encoding (see Input Type below)
cellFormula	true	Save formulae to the .f field **
cellHTML	true	Parse rich text and save HTML to the .h field
cellNF	false	Save number format string to the .z field
cellStyles	false	Save style/theme info to the .s field
cellDates	false	Store dates as type d (default is n) **
sheetStubs	false	Create cell objects for stub cells
sheetRows	0	If >0, read the first sheetRows rows **
bookDeps	false	If true, parse calculation chains
bookFiles	false	If true, add raw files to book object **
bookProps	false	If true, only parse enough to get book metadata **
bookSheets	false	If true, only parse enough to get the sheet names
bookVBA	false	If true, expose vbaProject.bin to vbaraw field **
password	""	If defined and file is encrypted, use password **
WTF	false	If true, throw errors on unexpected file features **

• cellFormula option only applies to formats that require extra processing to parse formulae (XLS/XLSB).
• Even if cellNF is false, formatted text will be generated and saved to .w
• In some cases, sheets may be parsed even if bookSheets is false.
• bookSheets and bookProps combine to give both sets of information
• Deps will be an empty object if bookDeps is falsy
• bookFiles behavior depends on file type:
  • keys array (paths in the ZIP) for ZIP-based formats
  • files hash (mapping paths to objects representing the files) for ZIP
  • cfb object for formats using CFB containers
• sheetRows-1 rows will be generated when looking at the JSON object output (since the header row is counted as a row when parsing the data)
• bookVBA merely exposes the raw vba object. It does not parse the data.
• cellDates currently does not convert numerical dates to JS dates.
• Currently only XOR encryption is supported. Unsupported error will be thrown for files employing other encryption methods.
• WTF is mainly for development. By default, the parser will suppress read errors on single worksheets, allowing you to read from the worksheets that do parse properly. Setting WTF:1 forces those errors to be thrown.

The defaults are enumerated in bits/84_defaults.js

Input Type

Strings can be interpreted in multiple ways. The type parameter for read tells the library how to parse the data argument:

type	expected input
"base64"	string: base64 encoding of the file
"binary"	string: binary string (n-th byte is data.charCodeAt(n))
"buffer"	nodejs Buffer
"array"	array: array of 8-bit unsigned int (n-th byte is data[n])
"file"	string: filename that will be read and processed (nodejs only)

Guessing File Type

Excel and other spreadsheet tools read the first few bytes and apply other heuristics to determine a file type. This enables file type punning: renaming files with the .xls extension will tell your computer to use Excel to open the file but Excel will know how to handle it. This library applies similar logic:

Byte 0	Raw File Type	Spreadsheet Types
0xD0	CFB Container	BIFF 5/8 or password-protected XLSX/XLSB
0x09	BIFF Stream	BIFF 2/3/4/5
0x3C	XML/HTML	SpreadsheetML or Flat ODS or UOS1 or HTML
0x50	ZIP Archive	XLSB or XLSX/M or ODS or UOS2
0xFE	UTF8 Text	SpreadsheetML or Flat ODS or UOS1

Writing Options

The exported write and writeFile functions accept an options argument:

Option Name	Default	Description
type		Output data encoding (see Output Type below)
cellDates	false	Store dates as type d (default is n)
bookSST	false	Generate Shared String Table **
bookType	"xlsx"	Type of Workbook (see below for supported formats)
sheet	""	Name of Worksheet for single-sheet formats **
compression	false	Use ZIP compression for ZIP-based formats **

• bookSST is slower and more memory intensive, but has better compatibility with older versions of iOS Numbers
• The raw data is the only thing guaranteed to be saved. Formulae, formatting, and other niceties may not be serialized (pending CSF standardization)
• cellDates only applies to XLSX output and is not guaranteed to work with third-party readers. Excel itself does not usually write cells with type d so non-Excel tools may ignore the data or blow up in the presence of dates.

Supported Output Formats

For broad compatibility with third-party tools, this library supports many output formats. The specific file type is controlled with bookType option:

bookType	file ext	container	sheets	Description
xlsx	.xlsx	ZIP	multi	Excel 2007+ XML Format
xlsm	.xlsm	ZIP	multi	Excel 2007+ Macro XML Format
xlsb	.xlsb	ZIP	multi	Excel 2007+ Binary Format
ods	.ods	ZIP	multi	OpenDocument Spreadsheet
biff2	.xls	none	single	Excel 2.0 Worksheet format
fods	.fods	none	multi	Flat OpenDocument Spreadsheet
csv	.csv	none	single	Comma Separated Values

• compression only applies to formats with ZIP containers.
• Formats that only support a single sheet require a sheet option specifying the worksheet. If the string is empty, the first worksheet is used.

Output Type

The type argument for write mirrors the type argument for read:

type	output
"base64"	string: base64 encoding of the file
"binary"	string: binary string (n-th byte is data.charCodeAt(n))
"buffer"	nodejs Buffer
"file"	string: name of file to be written (nodejs only)

Utility Functions

The sheet_to_* functions accept a worksheet and an optional options object.

The examples are based on the following worksheet:

XXX| A | B | C | D | E | F | G |
---+---+---+---+---+---+---+---+
 1 | S | h | e | e | t | J | S |
 2 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
 3 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |

Formulae Output

XLSX.utils.sheet_to_formulae generates an array of commands that represent how a person would enter data into an application. Each entry is of the form A1-cell-address=formula-or-value. String literals are prefixed with a ' in accordance with Excel. For the example sheet:

> var o = XLSX.utils.sheet_to_formulae(ws);
> o.filter(function(v, i) { return i % 5 === 0; });
[ 'A1=\'S', 'F1=\'J', 'D2=4', 'B3=3', 'G3=8' ]

CSV and general DSV Output

As an alternative to the writeFile CSV type, XLSX.utils.sheet_to_csv also produces CSV output. The function takes an options argument:

Option Name	Default	Description
FS	","	"Field Separator" delimiter between fields
RS	"\n"	"Record Separator" delimiter between rows

For the example sheet:

> console.log(XLSX.utils.sheet_to_csv(ws));
S,h,e,e,t,J,S
1,2,3,4,5,6,7
2,3,4,5,6,7,8
> console.log(XLSX.utils.sheet_to_csv(ws, {FS:"\t"}));
S	h	e	e	t	J	S
1	2	3	4	5	6	7
2	3	4	5	6	7	8
> console.log(X.utils.sheet_to_csv(_ws,{FS:":",RS:"|"}));
S:h:e:e:t:J:S|1:2:3:4:5:6:7|2:3:4:5:6:7:8|

JSON

XLSX.utils.sheet_to_json and the alias XLSX.utils.sheet_to_row_object_array generate different types of JS objects. The function takes an options argument:

Option Name	Default	Description
raw	false	Use raw values (true) or formatted strings (false)
range	from WS	Override Range (see table below)
header		Control output format (see table below)

• raw only affects cells which have a format code (.z) field or a formatted text (.w) field.
• If header is specified, the first row is considered a data row; if header is not specified, the first row is the header row and not considered data.
• When header is not specified, the conversion will automatically disambiguate header entries by affixing _ and a count starting at 1. For example, if three columns have header foo the output fields are foo, foo_1, foo_2

range is expected to be one of:

range	Description
(number)	Use worksheet range but set starting row to the value
(string)	Use specified range (A1-style bounded range string)
(default)	Use worksheet range (ws['!ref'])

header is expected to be one of:

header	Description
1	Generate an array of arrays
"A"	Row object keys are literal column labels
array of strings	Use specified strings as keys in row objects
(default)	Read and disambiguate first row as keys

For the example sheet:

> console.log(X.utils.sheet_to_json(_ws));
[ { S: 1, h: 2, e: 3, e_1: 4, t: 5, J: 6, S_1: 7 },
  { S: 2, h: 3, e: 4, e_1: 5, t: 6, J: 7, S_1: 8 } ]

> console.log(X.utils.sheet_to_json(_ws, {header:1}));
[ [ 'S', 'h', 'e', 'e', 't', 'J', 'S' ],
  [ 1, 2, 3, 4, 5, 6, 7 ],
  [ 2, 3, 4, 5, 6, 7, 8 ] ]

> console.log(X.utils.sheet_to_json(_ws, {header:"A"}));
[ { A: 'S', B: 'h', C: 'e', D: 'e', E: 't', F: 'J', G: 'S' },
  { A: 1, B: 2, C: 3, D: 4, E: 5, F: 6, G: 7 },
  { A: 2, B: 3, C: 4, D: 5, E: 6, F: 7, G: 8 } ]
> console.log(X.utils.sheet_to_json(_ws, {header:["A","E","I","O","U","6","9"]}));
[ { '6': 'J', '9': 'S', A: 'S', E: 'h', I: 'e', O: 'e', U: 't' },
  { '6': 6, '9': 7, A: 1, E: 2, I: 3, O: 4, U: 5 },
  { '6': 7, '9': 8, A: 2, E: 3, I: 4, O: 5, U: 6 } ]

Example showing the effect of raw:

> _ws['A2'].w = "1";                         // set A2 formatted string value
> console.log(X.utils.sheet_to_json(_ws, {header:1}));
[ [ 'S', 'h', 'e', 'e', 't', 'J', 'S' ],
  [ '1', 2, 3, 4, 5, 6, 7 ],                 // <-- A2 uses the formatted string
  [ 2, 3, 4, 5, 6, 7, 8 ] ]
> console.log(X.utils.sheet_to_json(_ws, {header:1, raw:true}));
[ [ 'S', 'h', 'e', 'e', 't', 'J', 'S' ],
  [ 1, 2, 3, 4, 5, 6, 7 ],                   // <-- A2 uses the raw value
  [ 2, 3, 4, 5, 6, 7, 8 ] ]

File Formats

Despite the library name xlsx, it supports numerous spreadsheet file formats:

Format	Read	Write
Excel Worksheet/Workbook Formats	:-----:	:-----:
Excel 2007+ XML Formats (XLSX/XLSM)	⭕	⭕
Excel 2007+ Binary Format (XLSB BIFF12)	⭕	⭕
Excel 2003-2004 XML Format (XML "SpreadsheetML")	⭕	⭕
Excel 97-2004 (XLS BIFF8)	⭕
Excel 5.0/95 (XLS BIFF5)	⭕
Excel 4.0 (XLS/XLW BIFF4)	⭕
Excel 3.0 (XLS BIFF3)	⭕
Excel 2.0/2.1 (XLS BIFF2)	⭕	⭕
Excel Supported Text Formats	:-----:	:-----:
Delimiter-Separated Values (CSV/TSV/DSV)		⭕
Other Workbook/Worksheet Formats	:-----:	:-----:
OpenDocument Spreadsheet (ODS)	⭕	⭕
Flat XML ODF Spreadsheet (FODS)	⭕	⭕
Uniform Office Format Spreadsheet (标文通 UOS1/UOS2)	⭕
Other Common Spreadsheet Output Formats	:-----:	:-----:
HTML Tables	⭕

Excel 2007+ XML (XLSX/XLSM)

XLSX and XLSM files are ZIP containers containing a series of XML files in accordance with the Open Packaging Conventions (OPC). The XLSM filetype, almost identical to XLSX, is used for files containing macros.

The format is standardized in ECMA-376 and later in ISO/IEC 29500. Excel does not follow the specification, and there are additional documents discussing how Excel deviates from the specification.

Excel 2.0-95 (BIFF2/BIFF3/BIFF4/BIFF5)

BIFF 2/3 XLS are single-sheet streams of binary records. Excel 4 introduced the concept of a workbook (XLW files) but also had single-sheet XLS format. The structure is largely similar to the Lotus 1-2-3 file formats. BIFF5/8/12 extended the format in various ways but largely stuck to the same record format.

There is no official specification for any of these formats. Excel 95 can write files in these formats, so record lengths and fields were backsolved by writing in all of the supported formats and comparing files. Excel 2016 can generate BIFF5 files, enabling a full suite of file tests starting from XLSX or BIFF2.

Excel 97-2004 Binary (BIFF8)

BIFF8 exclusively uses the Compound File Binary container format, splitting some content into streams within the file. At its core, it still uses an extended version of the binary record format from older versions of BIFF.

The MS-XLS specification covers the basics of the file format, and other specifications expand on serialization of features like properties.

Excel 2003-2004 (SpreadsheetML)

Predating XLSX, SpreadsheetML files are simple XML files. There is no official and comprehensive specification, although MS has released whitepapers on the format. Since Excel 2016 can generate SpreadsheetML files, backsolving is pretty straightforward.

Excel 2007+ Binary (XLSB, BIFF12)

Introduced in parallel with XLSX, the XLSB filetype combines BIFF architecture with the content separation and ZIP container of XLSX. For the most part nodes in an XLSX sub-file can be mapped to XLSB records in a corresponding sub-file.

The MS-XLSB specification covers the basics of the file format, and other specifications expand on serialization of features like properties.

OpenDocument Spreadsheet (ODS/FODS) and Uniform Office Spreadsheet (UOS1/2)

ODS is an XML-in-ZIP format akin to XLSX while FODS is an XML format akin to SpreadsheetML. Both are detailed in the OASIS standard, but tools like LO/OO add undocumented extensions.

UOS is a very similar format, and it comes in 2 varieties corresponding to ODS and FODS respectively. For the most part, the difference between the formats lies in the names of tags and attributes.

Comma-Separated Values

Excel CSV deviates from RFC4180 in a number of important ways. The generated CSV files should generally work in Excel although they may not work in RFC4180 compatible readers.

HTML

Excel HTML worksheets include special metadata encoded in styles. For example, mso-number-format is a localized string containing the number format. Despite the metadata the output is valid HTML, although it does accept bare & symbols.

Testing

make test will run the node-based tests. By default it runs tests on files in every supported format. To test a specific file type, set FMTS to the format you want to test. Feature-specific tests are avaialble with make test_misc

$ make test        # run full tests
$ make test_xls    # only use the XLS test files
$ make test_xlsx   # only use the XLSX test files
$ make test_xlsb   # only use the XLSB test files
$ make test_xml    # only use the XLSB test files
$ make test_ods    # only use the XLSB test files

To enable all errors, set the environment variable WTF=1:

$ make test        # run full tests
$ WTF=1 make test  # enable all error messages

Flow and JSHint/JSCS checks are available:

$ make lint        # JSHint and JSCS checks
$ make flow        # make lint + Flow checking

To run the in-browser tests, clone the repo for oss.sheetjs.com and replace the xlsx.js file (then fire up the browser and go to stress.html):

$ cp xlsx.js ../SheetJS.github.io
$ cd ../SheetJS.github.io
$ simplehttpserver # or "python -mSimpleHTTPServer" or "serve"
$ open -a Chromium.app http://localhost:8000/stress.html

Tested Environments

• NodeJS 0.8, 0.9, 0.10, 0.11, 0.12, 4.x, 5.x, 6.x, 7.x
• IE 6/7/8/9/10/11 (IE6-9 browsers require shims for interacting with client)
• Chrome 24+
• Safari 6+
• FF 18+

Tests utilize the mocha testing framework. Travis-CI and Sauce Labs links:

• https://travis-ci.org/SheetJS/js-xlsx for XLSX module in nodejs
• https://travis-ci.org/SheetJS/SheetJS.github.io for XLS* modules
• https://saucelabs.com/u/sheetjs for XLS* modules using Sauce Labs

Test Files

Test files are housed in another repo.

Running make init will refresh the test_files submodule and get the files.

Contributing

Due to the precarious nature of the Open Specifications Promise, it is very important to ensure code is cleanroom. Consult CONTRIBUTING.md

The xlsx.js file is constructed from the files in the bits subdirectory. The build script (run make) will concatenate the individual bits to produce the script. Before submitting a contribution, ensure that running make will produce the xlsx.js file exactly. The simplest way to test is to add the script:

$ git add xlsx.js
$ make clean
$ make
$ git diff xlsx.js

To produce the dist files, run make dist. The dist files are updated in each version release and should not be committed between versions.

License

Please consult the attached LICENSE file for details. All rights not explicitly granted by the Apache 2.0 License are reserved by the Original Author.

References

ISO/IEC 29500:2012(E) "Information technology — Document description and processing languages — Office Open XML File Formats"

OSP-covered specifications:

• [MS-XLSB]: Excel (.xlsb) Binary File Format
• [MS-XLSX]: Excel (.xlsx) Extensions to the Office Open XML SpreadsheetML File Format
• [MS-OE376]: Office Implementation Information for ECMA-376 Standards Support
• [MS-CFB]: Compound File Binary File Format
• [MS-XLS]: Excel Binary File Format (.xls) Structure Specification
• [MS-ODATA]: Open Data Protocol (OData)
• [MS-OFFCRYPTO]: Office Document Cryptography Structure
• [MS-OLEDS]: Object Linking and Embedding (OLE) Data Structures
• [MS-OLEPS]: Object Linking and Embedding (OLE) Property Set Data Structures
• [MS-OSHARED]: Office Common Data Types and Objects Structures
• [MS-ODRAW]: Office Drawing Binary File Format
• [MS-ODRAWXML]: Office Drawing Extensions to Office Open XML Structure
• [MS-OVBA]: Office VBA File Format Structure
• [MS-CTXLS]: Excel Custom Toolbar Binary File Format
• [MS-XLDM]: Spreadsheet Data Model File Format
• [MS-EXSPXML3]: Excel Calculation Version 2 Web Service XML Schema
• [XLS]: Microsoft Office Excel 97-2007 Binary File Format Specification

Open Document Format for Office Applications Version 1.2 (29 September 2011)

Worksheet File Format (From Lotus) December 1984

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