C, R, and O in this spoonful of Alphabet Soup for a taste of Conversion Rate Optimization.

What is Conversion Rate Optimization?

Conversion Rate Opitmization, or CRO, is the process of continually improving your on-page experience for users such that you increase the rate at which your users are taking desired actions (conversions). A conversion might be purchasing a product, signing up for an email newsletter, submitting a website form, or producing an inbound phone call, for example. A CRO campaign is likely to focus on a multitude of aspects including:

1. On-page content structure and meaning
2. Calls-to-action 
3. Website navigation structure
4. Page speed and performance
5. Design and aesthetic
6. Accessibility
7. Ad Copy if applicable

CRO is a strategy that relies on a commitment to a continual practice of learning from data and optimizing with the use of A/B testing.

Your conversion rate is calculated by dividing the number of conversions by the number of visitors and multiplying by 100 for a percentage rate. If you have 10,000 visitors in one month and you added 200 email subscribers it would work out to two percent.

200 subscribers / 10,000 visitors  =  0.02  X  100  =  2% conversion rate.

A CRO campaign is made possible by a fairly strong flow of traffic. If your site has very few visitors it will be difficult to reach statistical signifigance and a proper A/B test may need to run for a long period of time before you could make truly informed choices.

There are a number of free calculators that can help you determine how long a single test needs to run before reaching statistical signifigance. Nabler, Optimizly, and Unbounce are a few.

Looking at the Unbounce calculator they describe the Minimal Detectable Effect as Desired Lift. Essentially this percentage is a measure of deviation from your baseline conversion rate that you want to measure. The smaller a change you want to detect, the larger amount of traffic you need to apply for your A/B test.

In our example, if we wanted to know with certainty that our A/B test page provided a 30% lift in conversions then we would need 1000 page visitors a day for 17 days to be sure. That same calculation with only 100 visitors per day shows how low-traffic sites have a difficult job for CRO.

In the case of low-traffic sites you are generally best off to spend upfront time on the design of your landing page(s) according to best practices and either have patience for accuracy in results or accept a much wider lift, which means you are only measuring home run changes in A/B and not the smaller incremental changes that can add up more quickly. 

A CRO campaign that continually, incrementally improves the rate at which your visitors convert means paid search campaigns experience lowering costs per conversion, your acquisition costs are lowered, and it becomes easier to gain more value from your overall traffic. CRO is the best option for growing from your already-established traffic and often is more cost-effective than trying to purchase new traffic entirely.