Help with dimensions

[fireweed24]

Can you help figure out what size stones I would need to get the look of this ratio. I have a 7mm round center stone. What size side stones would I need if I wanted my ring to look like this leon? I was thinking maybe 3.5X5 mm. I like the chunkier pear look.

I hope the pic shows up sorry I don't know whose ring this is

 

[stone-cold11]

This? Just not the diameter ratio of the set you prefer and then calculate, by proportions, to your stone size.

This being the approx size of round brilliant, by carat weight.

 

[fireweed24]

Thanks for the chart. I ordered 4X3 mm pears, but I thought they were too small so I returned them. It is just so hard for me to imagine what size is best. I just love the ratio in the pic. I was thinking of ordering 4x5mm but I am afraid that will be too large.