Conversion rate is the share of visitors, sessions, or clicks that complete a defined action — a purchase, sign-up, or lead — calculated as (conversions ÷ total) × 100. It is the hinge metric that turns traffic into outcomes.
Why it matters for agencies
Small movements in conversion rate compound through the whole funnel: doubling it halves your effective CPA and CPL without touching media spend. Because it is so leveraged, it is where landing-page, offer, and audience optimisation pay off fastest. Always define the denominator precisely — visitors, sessions, or clicks give very different numbers.
Run the numbers with the free conversion rate calculator.