Indesign Math Plugin Free May 2026

Need 10 text frames to be 20px wider? Select them all. In the Width field, type + 20. Every selected frame grows by 20px.

It is important to note that "completely free, open-source, forever" plugins for InDesign are rare. Developers invest significant time because InDesign's SDK (Software Development Kit) is complex. However, several developers offer fully functional free tiers, trial versions without time limits (with watermarks), or donation-ware.

Here are the top contenders for an InDesign math plugin free solution. indesign math plugin free

If you cannot find a plugin that fits your needs, you can write your own free script. InDesign has a built-in Scripting engine that supports AppleScript (Mac) or ExtendScript (JavaScript).

Here is a free, copy-paste script that sums a column of numbers in a table: Need 10 text frames to be 20px wider

// Free Math Script for InDesign
// Select a table cell at the bottom of a column and run this.
var cell = app.selection[0];
var table = cell.parent;
var colIndex = cell.column;
var total = 0;
for (var i = 0; i < table.rows.length - 1; i++) 
var value = parseFloat(table.rows[i].cells[colIndex].contents);
if (!isNaN(value)) total += value;
 To use this: Copy the code into a
cell.contents = total;

To use this: Copy the code into a text editor, save it as SumColumn.jsx, install it via the Scripts panel (as above). You now have a custom, free math tool.

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