The short version: conversion rate on Shopify is simply the percentage of store visitors who complete a purchase, calculated as orders divided by sessions, times 100. It matters because it tells you how well your store turns traffic into money, but it’s not the whole story and treating it like the only metric that matters has cost more Shopify owners their margins than any algorithm change ever has. The actual maths behind it If 2,000 people visit your Shopify store in a month and 40 of them buy something, your conversion rate is 2%. Shopify calculates this for you automatically under Analytics, and it breaks it down by device, by traffic source, and by stage of checkout, which is where the useful information lives, not in the headline percentage. I had a client last year, a small candle brand out of Manchester turning over roughly £18,000 a month, who was convinced her store was broken because her overall conversion rate sat at 1.