An “123” file is typically associated with spreadsheet files created by Lotus 1-2-3, a spreadsheet software that was popular in the early days of personal computing. The .123 file extension is used for spreadsheet files created by Lotus 1-2-3, and these files contain data arranged in rows and columns.

How to open a 123 file:

1. Microsoft Excel:

2. LibreOffice Calc:

3. WPS Office:

4. Online Converters:

Various apps that use files with 123 extension: