Find out how much you should spend based on math rather than hearsay.

OK, I always see questions in the forum asking how much you should spend testing an offer.

Rather than basing your budget on an answer from someone who may or may not know what they are talking about, try doing this:

Two Examples.

Example 1- How to determine the confidence interval of an already ran campaign.

Go to: Confidence Interval for Proportions Calculator

Now calculate your Confidence Internal (yes this is math but the website does it for you)

How to:

Step 1: Select your desired confidence level(I usually go with 90%)

Step 2: Let's say you ran a CPC test and had 100 clicks. Enter 100 into the sample size.

Step 3: Now let's say, from those 100 clicks you had 3 conversions.
Enter 3 into the observed survey result.

Now calculate.

In the example above, you can now determine that true population proportion ranges between .19% and 5.18%

Example 2 - How to estimate a desired sample size

Go here: Sample Size for Proportion Calculator

Step 1: Enter your desired confidence level (again, I usually use 90%)

Step 2: Enter your estimated conversion rate

Step 3: Enter your desired confidence interval (I typically use 2)

Now Calculate and you will see the minimum sample size needed.