What is conversion rate and how is it calculated
Conversion rate is the percentage of your website's visitors who complete the action you care about, such as buying or submitting a form, and you calculate it by dividing conversions by visits and multiplying by 100.
By Fernando Blanco Dosil · Updated November 2, 2026
The formula
Conversion rate = (conversions ÷ visits) × 100.
It looks trivial, but two decisions change the number and are worth writing down: what counts as a conversion and what you count as a visit. You can divide by sessions or by unique users. With sessions, someone who comes three times before buying counts as three visits; with users, as one. Neither is the right one, but if you switch halfway through the year you are comparing apples with oranges.
Worked example
An online coffee store in an ordinary month.
| Figure | Calculation | |
|---|---|---|
| Sessions in the month | 12,000 | |
| Completed orders | 240 | |
| Conversion rate | 2% | 240 ÷ 12,000 × 100 |
| Mobile only | 1.4% | 112 orders ÷ 8,000 sessions × 100 |
| Desktop only | 3.2% | 128 orders ÷ 4,000 sessions × 100 |
Made-up figures for the example. The overall number hides that mobile converts at half the rate of desktop.
Micro and macro conversions
The macro conversion is the business goal: an order, a booking, a qualified lead. It pays the bills and it should be what decides your tests.
Micro conversions are the steps before it: adding to cart, starting checkout, signing up for the newsletter, opening the size guide. They help you see where people get stuck, but be careful: a change can lift "Add to cart" clicks without selling a single extra order.
How Bixlow measures it
In Bixlow you define goals (a click, a submitted form, a confirmation URL or an event in your dataLayer), and every time a visitor completes one it counts as a conversion. In an A/B test, each conversion is credited to the version that visitor saw, and a Bayesian statistics engine compares each version's conversion rate before giving a verdict.