The core digital marketing metrics are click-through rate, conversion rate, cost per click, cost per acquisition, customer acquisition cost, return on ad spend, customer lifetime value and churn. Each has a simple formula, and strong assignments use them to judge whether a campaign met its objectives.
| Metric | Formula |
|---|
| Click-through rate (CTR) | Clicks ÷ impressions × 100 |
| Conversion rate | Conversions ÷ visitors × 100 |
| Cost per click (CPC) | Ad spend ÷ clicks |
| Cost per acquisition (CPA) | Ad spend ÷ conversions |
| Customer acquisition cost (CAC) | Total sales and marketing cost ÷ new customers |
| Return on ad spend (ROAS) | Revenue from ads ÷ ad spend |
| Customer lifetime value (CLV) | Average order value × orders per year × years as a customer × margin |
| Churn rate | Customers lost ÷ customers at the start of the period × 100 |
Illustrative example: a customer spends £40 per order, orders 3 times a year for 2 years, at a 50% margin, so CLV = £40 × 3 × 2 × 50% = £120. If CAC is £30, the CLV:CAC ratio is £120 ÷ £30 = 4:1.
Tutors also cover SEO, paid search, social media, email and content marketing. See digital marketing help and advertising management.