117

.117Microsoft Excel 1.0 Spreadsheet

Microsoft · 1985

Developer
Microsoft
Category
Spreadsheets
MIME Type
application/vnd.ms-excel
First Released
1985
Open Format
No
File Signature
Not readily documented or consistently used as a reliable identifier.
At a Glance
.117
Microsoft Excel 1.0 Spreadsheet

A very old, proprietary spreadsheet file format from the initial release of Microsoft Excel for Macintosh.

Reviewed on April 28, 2026
Compression
Binary
Transparency
No
Editability
Low
Best for
Early spreadsheets

Key Features

  • Proprietary binary format for early Excel.
  • Supports basic spreadsheet data and formulas.
  • Exclusive to Microsoft Excel 1.0 on Macintosh.
  • Lacks modern features and cross-platform compatibility.

Best For

  • Storing very basic numerical and text data for early spreadsheets.
  • Serving as a historical data artifact.
  • Compatibility with the original Microsoft Excel 1.0 on Macintosh.

Less Ideal For

  • Sharing data between different spreadsheet applications.
  • Storing complex calculations or large datasets.
  • Collaborative work or modern data analysis.
  • Use on any platform other than early Macintosh.

Common Use Cases

  • Archival of extremely old spreadsheets from the mid-1980s.
  • Historical data recovery for users with legacy systems.
  • Rarely used for active data management or sharing.

How to Open It

  1. Attempt to open with a very old version of Microsoft Excel (e.g., Excel 1.0 for Mac) if available on compatible hardware or emulator.
  2. Use data recovery software or specialized tools that might support legacy Excel formats.
  3. Consult with data recovery specialists if the data is critical.
  4. Modern Excel versions or other spreadsheet programs are unlikely to open this format directly.

What is a .117 file?

The .117 file extension represents an early binary spreadsheet format used by Microsoft Excel version 1.0, released in 1985. This format was designed specifically for the original Macintosh version of Excel. It contained worksheet data, formulas, formatting, and charts. As it predates modern spreadsheet capabilities and cross-platform compatibility, it is rarely encountered today. Opening these files typically requires much older versions of Excel or specialized conversion tools that can interpret its proprietary structure.

Programs That Open .117 Files

PlatformProgram
macOSMicrosoft Excel 1.0PaidOfficial

Common Problems with .117 Files

⚠️ File cannot be opened by modern software.
Due to its proprietary and outdated nature, modern spreadsheet programs cannot read .117 files. Specialized legacy software or conversion tools are needed, which are difficult to find and use.
⚠️ Difficulty finding software to open the file.
This format is extremely rare. You may need to use an emulator for older operating systems and install the original Excel version, or seek out data recovery services.

Frequently Asked Questions

Is the .117 file format still used?

No, the .117 file format is obsolete and is not used for any current applications or data storage. It is a relic of the very first version of Microsoft Excel.

Can I open a .117 file in modern Microsoft Excel?

Unfortunately, modern versions of Microsoft Excel (like Excel 2019 or Microsoft 365) cannot open .117 files. The format is too old and fundamentally different from current spreadsheet standards.

What is the difference between .117 and .XLS files?

The .117 file is from Excel 1.0, while .XLS was used for later versions (Excel 97-2003). While both are older binary formats, .XLS is more recent and widely recognized as a legacy Excel format, whereas .117 is even more archaic.

Technical Details

The .117 format is a binary file structure proprietary to Microsoft. It contains data in a specific, uncompressed layout that includes cells, their values, formulas, and basic formatting. Due to its age and limited scope, it lacks many features found in modern spreadsheet files like advanced charting or macro support.

Did You Know?

The .117 extension was used because the primary spreadsheet file extension at the time was typically '.XL', and Microsoft was experimenting with different suffixes.
This format predates widespread adoption of graphical user interfaces on PCs, making its release on the Macintosh a significant technological step.

Security Information

As an obsolete file format from the 1980s, .117 files are generally considered low-risk in terms of modern malware. However, always exercise caution when opening any file from an unknown source. Ensure your system is protected with up-to-date antivirus software.

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