Files with wk1 extension are spreadsheets saved in old Lotus 1-2-3 office program. These files were used in version 2.X.

There is one other file type using
the WK1 file extension!

wk1 icon.wk1 - Autodesk hydro data

Detailed description

Software that open wk1 file

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WK1 file extension - Lotus 1-2-3 version 2.x spreadsheet

What is wk1 file? How to open wk1 files?

File type specification:

Spreadsheet and workbook file type icon Spreadsheet and workbook file type

wk1 file icon: wk1 filetype icon

File extension wk1 is was used for the default document file type in Lotus 1-2-3 version 2.x from early 1990s.

A .wk1 files were used as the default spreadsheet format of  Lotus 1-2-3 version 2.x including, rows and columns, formulas etc.

MIME types:

This wk1 file type entry was marked as obsolete and no longer supported file format.

This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.

Updated: December 1, 2023

The default software associated to open wk1 file:

Lotus 1-2-3 icon

IBM logoLotus 1-2-3  Microsoft Windows software

Company or developer:

IBM Lotus 1-2-3 is spreadsheet application very popular in 80s and 90s of 20th century. It was released for Microsoft Windows, MS-DOS, Mac OS and OS/2. In 2002 IBM stopped the developing of the IBM Lotus 1-2-3. In the latest versions is Lotus 1-2-3 fully compatible with Microsoft Excel.

Help how to open:

Use Lotus 1-2-3 version 2.x or later to open the .wk1 files.

Also some modern spreadsheets programs can still open the .wk1 files. However the latest versions of Microsoft Excel from version 2007 no longer support that format. You can have luck with any earlier version of Excel, but you will probably lose most of the formatting from the .wk1 files.

How to convert:

You can open *.wk1 in Microsoft Excel and save it to another file format. You will probably lose formatting.

Find conversions from wk1 file:

wk1 to 123

wk1 to csv

wk1 to mdb

wk1 to pdf

wk1 to txt

wk1 to xls

wk1 to xlsx

Find converter to wk1 file type:

123 to wk1

ods to wk1

wk! to wk1

wks to wk1

wq1 to wk1

xls to wk1

xlsx to wk1

List of software applications associated to the .wk1 file extension

Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open wk1 file, edit wk1 file, convert wk1 file, view wk1 file, play wk1 file etc. (if exist software for corresponding action in's database).

Click on the tab below to simply browse between the application actions, to quickly get a list of recommended software, which is able to perform the specified software action, such as opening, editing or converting wk1 files.

Software that open wk1 file - Lotus 1-2-3 version 2.x spreadsheet

Programs supporting the exension wk1 on the main platforms Windows, Mac, Linux or mobile. Click on the link to get more information about listed programs for open wk1 file action.

Microsoft Windows:

Main software associated with wk1 file by default:
Lotus 1-2-3 small icon Lotus 1-2-3
Other suggested software:
Microsoft Excel small icon Microsoft Excel
Corel Quattro Pro small icon Corel Quattro Pro

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