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Convert 123 to xltx

  1. Download and install the latest version of Filestar.

  2. Right click on one or more 123 file(s) on your desktop and select Convert with Filestar.

  3. Type convert to xltx in the search box.

  4. Press Convert.

Or let an AI agent do it: filestarcli -i file.123 -c "convert to xltx" (how).

Let your AI agent convert 123 to XLTX

Claude Code, Codex, Cursor and other agents can do this on your computer with Filestar. Your files stay on your machine. It works on Windows, macOS only.

Install Filestar and add it to your agents:

npm install -g filestar
filestarcli agent install

Or add it in one click:

Claude Code:

claude mcp add filestar -- npx -y [email protected] mcp

Then ask your agent:

“Convert the 123 files in my Downloads folder to XLTX”

Or run it yourself:

filestarcli -i file.123 -c "convert to xltx"

Runs on your computer, so your files stay on it. Works on Windows and macOS. 50 free conversions with the npm install, no account needed.

Can my AI agent convert 123 to XLTX?

Yes. Install the Filestar CLI with npm install -g filestar and your agent can run filestarcli -i file.123 -c "convert to xltx" on your computer, so your files stay on it.

Using Filestar With AI Agents → · Download SKILL.md

What is the difference between .123 and .xltx?

Name
Lotus 1-2-3 Spreadsheet
Excel Open XML Spreadsheet Template
Extension
.123
.xltx
Format
Binary
Binary
Category
Spreadsheet
Spreadsheet
Developer
IBM
Microsoft
Description
The 123 file format is a proprietary file format developed by the Lotus Development Corporation for use with its Lotus 1-2-3 spreadsheet software. It is a binary file format, which means that it stores data in a binary format that is not easily readable by humans.
An XLTX file is a template created by Microsoft Excel, a program used for creating spreadsheets.
MIME Type
application/vnd.lotus-1-2-3
application/vnd.openxmlformats-officedocument.spreadsheetml.template
Sample
sample.123
sample.xltx
Wikipedia
.123 on Wikipedia
.xltx on Wikipedia

Convert 123 To Xltx Today

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