If you are not using a logo, or you decide to use the logo with the text-based site title, you can change the title size.
- Go to Appearance > Customize > Site Identity
- Look for the Site Title Font Size setting.
- Move the slider to increase or decrease your logo image size.
- Click the Publish button.
To revert the site title size back to the default setting, click on the small circular arrow icon next to the slider.