Conversion rate: how to calculate it and read it properly

Conversion rate is the share of your visitors who complete a desired goal, such as a purchase or a submitted form. You calculate it by dividing the number of conversions by the number of visitors and multiplying by 100. A level of 2 to 5 per cent can look low, but measured against the wrong figures it can be downright misleading. Here is how to calculate it properly and improve it across every channel at once.

In this post we look at what conversion rate is and how to use the metric to grow your sales.

• Conversion rate is not always the most important metric
• Read wrongly, conversion rate can be actively counterproductive
• At the same time, raising your conversion rate is essential to getting results online

Sunbird is a search marketing agency with 14 years in search: SEO, Google Ads and the measurement behind them. Here we share what we have learnt.

Conversion rate shows what share of your visitors complete a conversion (a desired goal).

It is an important KPI (key performance indicator), used to judge whether a website is selling well or not.

Also known as: conversion ratio, CVR.

You decide what counts as a conversion. As a rule, it is when a visitor does something you want them to do on your website.

Conversions are usually split into macro conversions (strong signals) and micro conversions (weak signals).

• Purchase in an online shop
• Form submitted
• Trial account created
• Click on an email address
• Click on a phone number

When people talk about conversion rate, they usually mean how often macro conversions happen. Phone and email clicks are sometimes left out, since they could just as easily come from existing customers.

• Clicked through to social media
• Subscribed to the newsletter
• Visited several pages
• Visited the contact page
• Added a product to the basket

You calculate a conversion rate by taking the number of times the conversions you want to measure have happened and dividing it by the total number of visitors.

Number of conversions / Number of visitors = Conversion rate

Conversion rate is stated as a percentage, so multiply the figure from the equation above by 100.

You can calculate this conversion rate for several conversions together in the same report, or for each type of conversion on its own.

Make sure you use enough data. If you have few conversions, you may need to measure over a longer period. Otherwise the data is not significant, and so not reliable.

You can also measure the conversion rate for individual channels, for example Google Ads alone. How far you break it down depends on how many conversions you have. The aim is reliable data you can act on.

The short answer is that it depends on the industry, the channel and the price. But there are benchmarks to start from.

According to Contentsquare’s Digital Experience Benchmark (2024 edition, covering 2023), the average conversion rate across ecommerce sectors was 2.63 per cent.

What a normal ecommerce conversion rate is in any individual case is hard to say. We have seen conversion rates of 1 per cent that were considered very good and 3 per cent that were low.

In general, an online shop’s conversion rate falls as the price rises.

We find it more useful to measure ROAS, return on ad spend: what you get back for every pound you spend.

Doing that in Google Ads and other paid channels is usually straightforward. It gets harder once you factor in agency fees and staff costs.

Increasing the number of people who buy can, for example, lower your average order value. Our recommendation is to compare by ROAS and work towards raising it instead.

For a website without a shop, working out your conversion rate for macro conversions is more useful.

In our experience, a good conversion rate usually sits between 2 and 5 per cent.

If you offer a free trial account, though, you should be higher, possibly well above that range. That depends entirely on how the offer is set up and on the competition.

Conversion rates on mobile are generally much lower than on desktop. Contentsquare’s 2026 benchmark (comparing Q4 2024 with Q4 2025) puts desktop at 3.4 per cent and mobile web at around 2 per cent, even though desktop accounted for just 30 per cent of visits.

That does not necessarily mean mobile users are less inclined to buy. Friction often plays a large part: awkward forms on small screens, slower loading and payment steps that do not work smoothly. Many people also research on their phone and buy later on a computer.

So always compare mobile and desktop separately. If mobile sits far below your desktop figure, you know where the money is leaking.

The main value in measuring conversion rate is not comparing yourself with others. Comparing internally tells you more. For example:

• Comparing desktop and mobile
• Comparing channels such as organic traffic, paid traffic and social media
• Seeing how it rises or falls over time
• Comparing landing pages with each other
• It is essential for running A/B tests when you work systematically on raising your conversion rate

Web analytics tools such as GA4 no longer show your exact conversion rate. When visitors decline cookies, part of the session data never reaches GA4, and where Google Consent Mode v2 is in place, part of what you see is modelled rather than counted. (In the UK, the rules on cookies sit in PECR and the Information Commission enforces them.)

That means the number of transactions GA4 reports rarely matches reality. So what do you do about it?

• Use your ecommerce platform’s or ERP system’s own database as the record of actual purchases and revenue. It is the only source that counts every single order.
• Use GA4 to understand relative trends and behaviour, such as which channel performs and how mobile differs from desktop, not as the absolute truth on volumes.

In short: never count pounds in GA4. Count pounds in your ERP or order system and use GA4 to understand why the figures move.

For most businesses, conversion rate takes no account of lead quality or of what the visitor cost.

Treating every visitor and every conversion as equal gives a false picture.

Say you have started running Display advertising, where clicks are cheap but visitors are often not that interested. Your conversion rate will probably fall, while the number of enquiries may rise.

If the cost per conversion is good, you should keep the channel running even though the conversion rate drops.

So compare like with like. Acting on the wrong data can do real damage to your sales.

In B2B, counting submitted forms is not enough. An enquiry that looks expensive in the ad platform can be very profitable if it lands a deal worth tens of thousands of pounds. So send the real value from your CRM back to the ad platforms, so that bidding optimises towards real deals.

Tips for improving the quality of your enquiries:

• Check that the number of enquiries in your tracking matches the actual number.
• If the enquiries you receive vary in quality, add some kind of qualifier to your forms, for example whether the enquiry comes from a business or a private individual. In some cases you may not want to count one or the other at all.
• If you want to take quality into account, you can use offline conversion tracking. With that method, only the enquiries your sales team considers genuine are counted.

Most people reading about conversion rate naturally want to know what they can do to raise it.

Some of the methods we have seen raise conversion rates:

• Be very clear about what you do and why someone should choose you
• Give clear reasons to act now
• Write a clear call to action and try several different ways to convert
• Show previous work and testimonials
• Show the benefits of choosing you
• Review the mobile design

Conversion rate depends on how the page is built. These posts go deeper:

• What is a landing page? How to build one that converts
• Conversion rate optimisation (CRO): a practical guide to more leads

Comparing yourself with others is not what matters. Start from where you are and identify where you can improve. The aim is for every update to make you a little better, and for you to be able to weigh your digital channels against each other.

In our view, work on conversion rate is badly underrated. The costs are usually one-off, and every channel benefits. It can also help both your SEO and your Quality Score in Google Ads. We recommend an ongoing approach where you improve it at regular intervals.

Good luck with raising your conversion rate.

These are the questions we are asked most often about conversion rate.

Divide the number of conversions by the number of visitors and multiply by 100. If you have 100,000 visitors and 2,300 purchases, your conversion rate is 2.3 per cent. Use enough data: if you have few conversions, you need to measure over a longer period for the figure to be reliable.

It depends entirely on the industry and the channel. As a rough guide from our own work, anything under 1 per cent is usually seen as low for ecommerce, while a lead generation website should ideally be above 2 per cent. But a low figure is not automatically bad: if the cost per conversion is right, a channel with a low conversion rate can still be profitable.

Click-through rate measures the share of people who click on, for example, an ad or a search result. Conversion rate measures the share of those who land on the page and then complete a desired goal. CTR is about bringing the traffic in; conversion rate is about what that traffic does once it arrives.

Common causes are that you are getting cheaper, less purchase-ready traffic (through Display, for example), that your tracking has changed so that more or fewer events are recorded, or that something has broken in the checkout or the form. Check first whether it is the traffic that has changed or the conversion point itself that is leaking.

Book a free search audit and we will show you where your traffic is leaking and what can be done about it. If your figures do not add up in the first place, our measurement and analytics work makes sure you are counting the right things.