How does conversion optimisation differ from conversion rate optimisation?

It’s a subtle difference, but conversion optimisation is the broader concept—it’s improving conversions overall, through user experience, messaging, or design. Conversion rate optimisation (CRO), on the other hand, focuses specifically on improving the percentage of visitors who convert. To sum up, conversion optimisation looks at the big picture, while CRO is more data-centric, measuring and improving the actual rate of conversions through testing.