Definition
Conversion rate: definition and formula
The conversion rate is the proportion of visits that end in the intended action on a site, over a given period. The formula divides the number of actions counted by the number of visits in the same period. Its value depends entirely on the action chosen: a completed form, a qualified lead and a sale collected produce three different rates on the same site.
What the rate measures, and what it doesn't
The conversion rate tells you what share of visitors completes the action you decided to count. It says nothing about the value of that action or the quality of the traffic. A site fed by searches for its own name converts better than a site fed by discovery advertising, without being any better: it is the traffic mix that changes.
Choosing the denominator
The formula is simple, but its base varies from one tool to another. Sessions, users or visitors who reached the checkout can produce results that differ by a factor of two on the same data. Pick a base, write it down and keep it: a rate calculated on two different bases cannot be compared.
When the figure becomes readable
A conversion rate is a proportion measured on a sample: it carries a margin of error. Below a few hundred visits a month on the page in question, it can rise and fall from one month to the next with nothing changed on the site. To find out what a good rate is for your type of site, read our analysis of a good conversion rate.
Conversion rate = actions counted ÷ visits × 100
Actions and visits cover the same period. Always name the action counted and the visit base (sessions or users) next to the figure.
A site receives 3,000 visits in a month and 60 quote requests. Its conversion rate is 60 ÷ 3,000 = 2%. If the same site also counted newsletter sign-ups, the figure would rise without a single additional sale being closed (fictional example).
We read the conversion rate as a measuring instrument, not a goal. It is compared with your own history, on the same action and the same calculation base. An industry average published by a software vendor mixes definitions that cannot be compared.
The question that decides a budget lies elsewhere: how much one more percentage point is worth in monthly revenue. The rate is only one step in that calculation. An increase announced as a percentage also applies to the rate, never to revenue: a 35% increase on a 2% rate gives 2.7%.
Not to be confused with
- Conversion rate optimization
- Conversion rate optimization (CRO) is the work of raising this rate. The rate is the measurement; CRO is the discipline.
- CTR
- CTR (click-through rate) measures the share of people who click on an ad or a result after seeing it. The conversion rate starts after the visitor lands on the site.
- Close rate
- The close rate is the share of leads your sales team turns into sales. It is read in the CRM, not in the site's analytics tool.
Related concepts
- Conversion
- Conversion rate optimization
- A/B test
- Cart abandonment
- Form friction
- CTR
- Useful conversion threshold
Further reading
- Good conversion rate: what it is, and for which type of site
- CRO: what conversion rate optimization really fixes
- A/B testing: why most tests prove nothing
- Forms: the number of fields decides, not the number of steps
- Cart abandonment: what the Baymard Institute's 49 studies show
Related services
Frequently asked questions
Is the conversion rate calculated on sessions or on users?
Both bases exist in analytics tools. What matters is choosing one and keeping it over time: on the same data, they can give very different results.
Why is my conversion rate dropping while my sales are rising?
Most often, the traffic mix has changed. A discovery campaign brings visitors earlier in their decision: the number of visits grows faster than the number of conversions.
