You can use your web browser to see the exact dimensions of the image spaces on your site.

Most modern browsers have an option called "Inspect Element" which is accessible by right-clicking over an area of a website. When selecting this option, typically a panel comes up showing the HTML content and the dimensions of the area. Click on various page elements to see their size.

If you do not see an option to "Inspect Element" you may need to enable Developer Tools in your browser.

Recommended: Maximum 300px wide

Recommended: 3200 x 1320 px

Recommended: 1280 x 720, or 16:9 ratio