What is conversion rate optimization?

Conversion rate optimization (CRO) is the practice of increasing the percentage of website visitors who take a desired action — filling out a form, booking a demo, making a purchase, or signing up for a trial.

The conversion rate formula: (conversions / total visitors) × 100. A site with 10,000 monthly visitors and 200 form submissions has a 2% conversion rate. Increasing that to 3% gives you 100 more leads per month with zero additional traffic spend.

CRO methods, ranked by impact: 1) Value proposition clarity — can a visitor understand what you do and why they should care within 5 seconds? 2) CTA placement and copy — is the action obvious and compelling? 3) Form optimization — fewer fields = higher completion rates. Remove every field that isn't essential. 4) Social proof — testimonials, case studies, client logos, and metrics near decision points. 5) Page speed — every 100ms of delay reduces conversion by 1%.

Common mistakes: testing button colors instead of value propositions, redesigning before analyzing data, optimizing for clicks instead of revenue, and running A/B tests without enough traffic for statistical significance (you need ~1,000 conversions per variant).

Average B2B website conversion rate: 2.6%. Top performers: 5-10%. If you're below 2%, focus on fundamentals (speed, clarity, CTA) before running experiments.