Hello,
by default, the measuring tool of PDF24 Reader shows lengths both in metric units and in inches. Since version 11.21.0 you can choose which:
- In PDF24 Reader, open the "More" menu and click "Settings".
- On the Reader page, uncheck "Display SI units-based value in the measuring tool" and leave "Display inch-based value in the measuring tool" checked.
The measuring tool then shows inches only.
The rulers at the edge of the page can also use inches (since version 11.31.0): "More" menu > "Show ruler" > "Inch (in)".