I have a several cells with strings such as this one:

"John,Carla,Peter,John,Bob,Chris,Carla,Andrea"

I would like to count how many different people are named (i.e. how many unique values). The count for the string above would be 6. Note that the total amount of names in the strings can vary a lot. Some have only one name and the biggest one has 14 (where some can be duplicated). Some names have spaces in them (ex. "Peter Smith,Andrea,Carla Moore"), but we can rely on the commas to separate them.

I think the solution is to convert the string into an array and then use a combination of the formulas SUM, IF and FREQUENCY which I found online here, applied to that array.

However I don't know how to convert the string into an array (if that is the way to go).