Change Slide Number Size on the PowerPoint Slide Master
Make the slide numbers in your PowerPoint presentations stand out by increasing the size of the slide number font. To increase the font size, open the Master Slide and use one of two methods to change the slide number. Changes on the Slide Master are applied to every slide in your presentation. The Slide Master controls the look of an entire presentation, including the slide numbers. When you want every slide number to look the same, change the slide number in the Slide Master. To access the PowerPoint Slide Master:
Increase the Font Size to Change the PowerPoint Slide Number Size
There are two different ways to change the font size of the slide number placeholder. Both methods are quick and easy. For both methods, find the slide number placeholder first. Double-click the slide number placeholder to change the font size: Right-click on the slide number placeholder to change the font size: After you’ve selected a larger font size and are happy with your changes, select Close Master View to exit the Slide Master View. All the slides in your presentation are updated and display the larger slide number.