Click the "Select File" button above, and choose your WK1 file.
You'll see a preview.
Click the "Convert file to..." button to save your file in the format you want.
Convert WK1 to another file type
The converter easily converts your WK1 spreadsheets to various formats - free and online. No Lotus 1-2-3 or or other Spreadsheet software needed.
WK1 to XLS
WK1 to XLSX
WK1 to ODS
WK1 to CSV
WK1 to TSV
WK1 to TAB
WK1 to DIF
WK1 to SLK
WK1 to TXT
WK1 to SXI
WK1 to HTML
WK1 to POT
Convert a file to WK1
To convert other file formats to the "Legacy Spreadsheet File" file type, you need software like Lotus 1-2-3 or a similar tool.
About WK1 files
The .WK1 file is a legacy spreadsheet format created by Lotus 1-2-3, the dominant DOS-era business software developed by Lotus Development Corporation and later acquired by IBM. These files store grid data, cell formatting, basic formulas, and early macros. Historically, they were opened directly in Lotus 1-2-3. Today, dealing with .WK1 files is incredibly frustrating. The format is a proprietary, obsolete binary structure that modern web browsers and mobile devices cannot parse. Worse, modern versions of Microsoft Excel explicitly block .WK1 files by default in their Trust Center settings due to security vulnerabilities found in legacy file parsers. Keeping data locked in this format guarantees eventual data loss. To recover your historical data, you must convert it. For modern editing, data analysis, and software compatibility, convert .WK1 to XLSX or CSV. For immutable archiving, convert to PDF. Be aware that while cell values and basic formulas translate well, ancient Lotus macros and 1980s chart formatting will be lost. Drop your file here to view and convert it securely right in your browser - free, online, and without installing risky legacy software.
Use Convert.Guru to open and convert your WK1 file.
If you want to convert WK1 file to XLSM, XLSB, WK3 or NOTES, you can use Lotus 1-2-3 or similar software from the "Legacy Spreadsheet Data Storage" category. In the File menu, look for Save As… or Export….
To convert WQ1, XLSM, NOTES, QPW, WK3, WB2, WKS, XLSB, 123, XLS, WB1 or XLSX files to WK1, try Lotus 1-2-3 or another comparable tool in the "Legacy Spreadsheet Data Storage" category.
The WK1 Converter Story
The history of Convert.Guru began over 25 years ago in California with Tom Simondi’s file-format database. A former contributor to Space Shuttle development and a software pioneer of the 1980s, Simondi established a trusted resource for file type analysis that was even referenced by Microsoft Windows XP. Today, we use modern technology to process and convert thousands of file formats while continually improving our WK1 converter.