The border-spacing property determines the spacing between cells. This has no effect unless border-collapse is set to separate.

Below an example of two tables with different values to the border-spacing property:

https://s3-us-west-2.amazonaws.com/secure.notion-static.com/c328383a-c722-4ded-a23b-2fcc64c76e52/Untitled.png

The table on the left has border-spacing: 2px (default) while the one on the right has border-spacing: 8px.

Value | Description | —— | —— |<length> | This is the default behavior, though the exact value can vary between browsers.| <length> <length> | This syntax allows specifying separate horizontal and vertical values respectively.