.123 — Lotus 1-2-3 Spreadsheet

Lotus Software (IBM) · 1983

Developer

Lotus Software (IBM)

Key Features

Integrated spreadsheet, charting, and database functionalities.
Pioneered many features common in modern spreadsheet applications.
Efficient binary storage for its era.
Influential in the adoption of personal computers for business.

Best For

Archiving historical data from Lotus 1-2-3.
Understanding the evolution of spreadsheet software.
Users needing compatibility with very old business systems.

Less Ideal For

Modern collaborative work.
Complex data visualization needs.
Sharing with users unfamiliar with legacy formats.
New projects requiring advanced spreadsheet features.

Common Use Cases

Storing financial data and budgets.
Creating charts and graphs from data.
Managing simple databases and lists.
Performing calculations and data analysis.

How to Open It

Attempt to open with modern spreadsheet software like Microsoft Excel or LibreOffice Calc, which often have import filters for .123 files.
Search for dedicated Lotus 1-2-3 emulators or viewers if direct import fails.
Consider online file converter tools that may support .123 conversion to more common formats like .xlsx or .csv.

What is a .123 file?

The .123 file extension is primarily associated with Lotus 1-2-3, a groundbreaking spreadsheet program that was immensely popular in the early days of personal computing. It allowed users to organize, analyze, and present data in tabular form, incorporating features like charts and basic databases. While its dominance has waned with the rise of Microsoft Excel and Google Sheets, it laid the foundation for modern spreadsheet software and was a key application for business productivity.

Programs That Open .123 Files

Platform	Program
Windows	LibreOffice Calc	Free
	Microsoft Excel	Paid	Official
macOS	LibreOffice Calc	Free
	Microsoft Excel	Paid	Official
Linux	LibreOffice Calc	Free

How to Convert .123 Files

Format	Method
.XLSX	Microsoft Excel, LibreOffice Calc, Online Converters
.CSV	Microsoft Excel, LibreOffice Calc, Online Converters

Common Problems with .123 Files

⚠️ Cannot open .123 files directly in modern software.

Use import features in programs like Microsoft Excel or LibreOffice Calc, or use a file converter.

⚠️ Loss of formatting or formulas during conversion.

Ensure the conversion tool or software has good compatibility with the .123 format; manual review of converted files is recommended.

Frequently Asked Questions

Is Lotus 1-2-3 still available?▼

Lotus 1-2-3 is discontinued. While IBM may offer support for existing enterprise customers, it is not commercially sold or updated for general use.

Can I open .123 files on a Mac or Linux computer?▼

Yes, programs like LibreOffice Calc are available on macOS and Linux and can often import .123 files. Microsoft Excel for Mac can also be used.

What is the difference between .123 and .xlsx?▼

.123 is an older, proprietary binary format from Lotus 1-2-3, while .xlsx is the modern, XML-based format used by Microsoft Excel, offering more features and better interoperability.

Technical Details

Lotus 1-2-3 files are binary files structured to store worksheet data, formulas, formatting, and charts. The format was proprietary to Lotus Development Corporation and later IBM. While not as feature-rich as modern spreadsheets, it offered a robust integration of spreadsheet, graphing, and basic database capabilities for its time.

Did You Know?

Lotus 1-2-3 was one of the first 'killer applications' for personal computers, driving sales of IBM PCs.

Its name, '1-2-3', referred to its advertised integration of spreadsheet, graphing, and basic database functionalities.

Security Information

As a legacy file format, .123 files are generally considered safe. However, always be cautious when opening files from unknown sources, as with any file type. Ensure your software used for opening or converting them is up-to-date.