How to Change the Measurement Unit for Custom Paper Size in PDF Printing
Question details
The user wants to change the measurement unit displayed (e.g., from inches to millimeters) when creating or selecting a custom paper size for printing a PDF document.

- Product
- PDF Printer
- Device & OS
- not provided
- Scenario
- Setting up custom paper dimensions for printing a PDF file.
- Observed behavior
- The unit displayed in the custom paper size dialog does not match the desired measurement system, as it relies on the operating system's printing system rather than the PDF software's internal preferences.
Make sure to save your work and completely close your PDF reader before making system changes, so the new measurement units can be properly applied when you reopen the application.
Modify Your Operating System Regional Settings
Since PDF software often pulls printing measurements directly from the operating system, changing your OS regional settings will update the units in the print dialog.
The custom paper size dialog is controlled by the system's printing spooler. Changing the measurement system (from U.S. to Metric, or vice versa) at the OS level is the most reliable way to fix the display unit.
Navigate to the Control Panel or the main Settings app on your computer.
Go to the 'Time & Language' or 'Region' settings menu.
Locate the measurement system preference (often under 'Additional date, time, & regional settings' > 'Change date, time, or number formats') and select either Metric (for millimeters) or U.S. (for inches).
Close your PDF application completely and reopen it. Access the print dialog to verify that the custom paper size units have updated.

Change Units Directly in the Printer Driver Preferences
Some printer drivers allow you to override system defaults and set a specific measurement unit specifically for printing tasks.
Easily Manage Custom Paper Sizes and Print PDFs with WPS Office
WPS Office provides a highly compatible built-in PDF reader and editor that seamlessly integrates with your system's printing spooler, allowing you to easily adjust paper sizes, set up custom print properties, and manage documents effectively.
- 1. Open PDF in WPS Office: Launch WPS Office and open your PDF document.
- 2. Access the Print Menu: Click the 'Menu' button in the top left corner and select 'Print', or use the shortcut Ctrl+P.
- 3. Open Printer Properties: Select your target printer from the dropdown menu and click on the 'Properties' button to access custom paper size settings.
- 4. Configure and Print: Define your paper dimensions using the correct units, click 'OK', and hit 'Print' to finalize.

Frequently Asked Questions
Why doesn't changing the unit inside my PDF software apply to the print dialog?
The print dialog generally pulls measurement units directly from the operating system's printing spooler or the specific printer driver. This bypasses the PDF application's internal display preferences, meaning system-level changes are required.
How do I add a new custom paper size in Windows?
Open the Control Panel, navigate to 'Devices and Printers', select your printer, and click 'Print server properties' at the top of the window. Check the 'Create a new form' box, enter your custom dimensions, name the form, and save it.
Will changing the system measurement unit affect my other applications?
Yes. Changing the regional measurement system in your operating system will update the default units across all installed software that relies on the system's global settings, including word processors and spreadsheet tools.




