You can adjust slide sizes for your presentations.
- On your computer, open a presentation in Google Slides.
- Click File Page setup.
- To choose a size, click the Down arrow .
- Standard (4:3)
- Widescreen (16:9)
- Widescreen (16:9)
- Custom: Beneath 'Custom', enter a size and pick a unit of measurement (inches, centimetres, points or pixels).
- Click OK.