Customer Experience can be defined a lot of different ways, but there exist even more ways to measure it. Folks will obviously differ on what are the best Customer Experience measurements to use, with the most common form being NPS (Net Promoter Score). Below I’ll list some of what I believe are the best measurements to assess Customer Experience, but I should mention that there are many more beyond this, along with several proprietary indices.

Here are some of the common definitions to measure Customer Experience:

• NPS (Net Promoter Score): “How likely is it that you would recommend our company to a friend or colleague?” (Scale of 1-10). Promoters provide a score of 9 or 10, while Detractors give a score of 6 and below, and the NPS is calculated by subtracting the Detractor percentage from the Promoter percentage of Survey respondents.
• CES (Customer Effort Score): “How much effort did you have to put forth to accomplish X?” (Scale of 1-5)
  
• CSAT (Customer Satisfaction): “How satisfied are you with X?” (Scale of 1-5)
  
• LVC (Lifetime Value of a Customer): (Average Sale) multiplied by the (Averaged Number of Sales per Time Period) multiplied by the (Average Customer Retention Time).
• Customer Retention: Percentage of Previous Customers that purchased a product or service within a Time Period.
  
• Product Adoption: Adopters are a customer that purchases a new product or service. The Product Adoption Rate is the percentage of Product Adopters that are a part of the total number of Customers.
  
• Cost per Sale
• Referral Rate: Percentage of new Customers from referrals of existing Customers.
  
• Active Repeat Customers Rate: Percentage of repeat Customers over a defined time period.
  
• Profitable Customer Rate
• Wallet Share: Percentage of Revenue from Total Customer Spend
• Customer Churn Rate: (Customers at the start of Time Period – Customers at end of Time Period) / (Customers at the start of Time Period)
• VOE (Voice of Employee) or eNPS (Employee Net Promoter Score): “Would you recommend this company as a place to work to a friend?” (Scale of 1-10). Promoters provide a score of 9 or 10, while Detractors give a score of 6 and below, and the NPS is calculated by subtracting the Detractor percentage from the Promoter percentage of Survey respondents.

A great link with a fairly comprehensive list of Customer Experience metrics can be found here.