Important eCommerce Metrics to Check in 2026 and Beyond

The important eCommerce metrics are the numbers that tell you whether your store is healthy and growing: sales conversion rate, average order value, customer lifetime value, customer acquisition cost, retention and churn rates, repeat customer rate, Net Promoter Score, cart abandonment rate, and the email and ad metrics that feed them. Each one answers a different question, and together they show where your business is strong and where it leaks money.

There is an old management line, often credited to Peter Drucker: "If you can't measure it, you can't improve it." The Drucker Institute's archivists found no evidence that he said it, but the idea still rings true for anyone who runs an online store.

In that spirit, this article looks at the primary business metrics to track, how to calculate each one correctly, how often to check them, and how the way we measure eCommerce success has changed. If you want the metrics that describe on-site engagement, such as page views per visit and checkout abandonment, see our companion list of 10 eCommerce metrics to increase user engagement.

What are eCommerce metrics and KPIs?

Generally speaking, a metric is a system or standard of measurement. In eCommerce, a metric is a quantifiable measurement of your shop's performance. A KPI is the way you measure business initiatives, objectives or goals.

Pay attention to the difference between the two:

• KPIs measure progress toward specific goals (for example, increasing sales-qualified leads five times by the end of the quarter).
• Metrics measure the overall health of the business.
• A KPI is built from multiple metrics.

Unless it is tied to a bigger goal, a metric does not mean much. You might track your shop's social media followers, but if social media is not part of your business initiatives, that number should not matter much. Harvard Business School's Working Knowledge made the same point years ago in Start to Measure Your E-commerce Success (2004): measures have to fit each company's strategy and objectives.

In the lead-generation example above, the metrics to track could be accounts created, conversion rate and Net Promoter Score. A metric becomes a compass that shows whether you are on the right path when it contributes to a business objective.

How do you determine which eCommerce metrics matter for your business?

There are so many ways to collect data, even as third-party data disappears, that it would be foolish not to let metrics guide your business. However, many marketers fall into the trap of vanity metrics: numbers that make you feel good but make no difference to the business.

You must choose carefully when you select your measures of eCommerce success. Every business is unique, and a rising small business will have different objectives from an established enterprise. In general, though, businesses pick metrics that cover:

• The popularity of your products or brands
• How often shoppers buy your products
• Issues or friction in the checkout process
• How many shoppers come back for a second purchase
• How much revenue you earn each month

A useful test for any metric: if this number moved sharply next week, would you do something different? If the answer is no, it is probably a vanity metric for your business.

What are the most important eCommerce metrics?

When your results are not good enough, it can feel like you are shooting in the dark. You made all that effort, and for what? And more importantly, what could you have done better? This is where metrics save your sanity, by showing you exactly what needs to improve. The American Marketing Association's 5 E-Commerce Metrics to Watch (2020) covers several of the same measures.

Sales metrics

Sales conversion rate is the percentage of visitors who complete a purchase. Conversion can mean any action you want users to take, but here we only count visitors who made a purchase. Divide the number of purchases by the number of visitors (or sessions), then multiply by 100. Sales conversion rate shows how well your marketing brings the right people, how smooth your checkout is, and how persuasive your product pages are. See the conversion rate definition for more detail.

Average order value (AOV) is the average amount spent each time a customer places an order. Divide your revenue by your number of orders. Read more about average order value.

Customer value metrics

Customer lifetime value (CLV), one of our personal favorites, is the total revenue you can expect from a single customer during their relationship with your business. A simple version is AOV x purchases per year x average customer lifespan in years. For more precise methods, including margin-based and predictive CLV, read our guide to calculating CLV.

Customer acquisition cost (CAC) shows how much you pay for a new customer. To calculate your CAC, divide your total marketing and sales spend for a period by the number of new customers acquired in that period. CAC is most useful when you check it against CLV. If CAC is higher than CLV, your business is in trouble, because you are losing money on every customer you acquire.

Loyalty and satisfaction metrics

Customer retention rate shows the percentage of existing customers you keep over a fixed period. Take the number of customers at the end of the period, subtract the new customers you acquired during it, divide by the number of customers at the start, and multiply by 100. Subtracting new customers matters: without it, strong acquisition hides the customers you lost.

Churn rate is the rate at which your business loses customers or subscribers over a fixed period, and the mirror image of retention. Divide the number of customers lost during the period by the number of customers at the start, then multiply by 100. There is no single benchmark that fits every store, because churn depends on the category and on how often people naturally reorder. The lower your churn rate, the healthier your business. For how retention, churn and repeat purchase rate relate, see repeat purchase rate vs retention rate vs churn rate.

Repeat customer rate shows the percentage of customers who have come back to buy again. Divide the number of returning customers by the total number of customers in the period, then multiply by 100. Keeping an existing customer is generally cheaper than winning a new one, so you want this rate as high as possible.

Net Promoter Score (NPS) moves us into customer happiness. It shows how willing customers are to recommend you. Customers answer, on a scale of 0 to 10, how likely they are to recommend you. Subtract the percentage of Detractors (scores 0 to 6) from the percentage of Promoters (scores 9 and 10). The result ranges from -100 to +100. NPS matters because customer satisfaction supports the longevity of your business. When your score is negative, look for unhealthy patterns and fix the recurring problems that leave customers with a bitter taste. Our Net Promoter Score guide covers the survey in depth.

Cart abandonment rate is the percentage of shoppers who add items to their cart but leave without completing the purchase. Divide completed purchases by carts created, subtract the result from 1, and multiply by 100. The purchase is the step that crowns all your efforts up to that point. A high cart abandonment rate means you are losing people you already paid to attract, so look at the user experience and find the friction points that make prospects leave.

Marketing metrics

Email open rate matters because email is how most eCommerce businesses talk to their subscribers, customers or not. Divide unique opens by emails delivered, then multiply by 100. Open rate helps you judge whether subscribers care about your brand or only stay for discounts. Read it with caution: privacy features such as Apple Mail Privacy Protection can register opens that never happened, so clicks are the more reliable signal.

Click-through rate (CTR) is closely related to open rate and measures how many people click a specific link. The formula depends on the channel. For ads, divide clicks by impressions. For email, CTR is usually unique clicks divided by emails delivered; dividing clicks by unique opens gives a different metric, click-to-open rate (CTOR). State which one you use, because the two numbers are very different.

eCommerce metric formulas with a worked example

Here is one month of data for an example store, used for every formula below: 50,000 sessions, 1,000 orders, $80,000 in revenue, $20,000 in marketing spend, 4,000 carts created, 900 customers who bought (400 new, 500 returning), 2,000 customers at the start of the month and 2,100 at the end.

In this example the CLV to CAC ratio is $600 to $50, or 12 to 1, on a revenue basis. On a gross-margin basis the ratio would be much lower, which is why the LTV:CAC ratio is best calculated with margin.

How often should you plan and check eCommerce metrics?

Checking your eCommerce metrics means checking your eCommerce success. But success does not happen overnight, so do not be disappointed if you check your metrics daily and see no visible progress.

How often you plan your metrics depends on your management system. You might do a full review of your business quarterly or twice a year. Plan your metrics around your goals and revisit them as often as those goals require.

For example, if your objective is 200 leads per quarter, check all relevant metrics at least once a week. That way you avoid being surprised at the end of the quarter and can adapt quickly if things are not going your way.

Again, it all depends on the timeframe and complexity of your business objectives.

Why are eCommerce metrics important for your business?

Measuring progress matters as much in business as it does in your personal life. If you plan to run a marathon by the end of the year, you set goals and check your progress regularly. Otherwise you are left with a vague idea of how much to train, and you might injure yourself or fail to finish.

eCommerce businesses work by the same principle: you check your metrics and reports to make sure you reach your goals by the end of the timeframe. Metrics:

• provide an objective overview of how your business works
• reveal opportunities for improvement

Objective feedback is what grows your business. You cannot build a sales funnel on gut feelings; you need to look at the numbers and let them reveal the roadblocks. By the same logic, you cannot overinvest in acquisition if average order values are low and you do not get back the money you put in.

Metrics transform vague objectives into concrete plans that can be measured for efficiency. They tell you whether your strategies meet customers' needs or need to be improved. And they remove words like "good quality" and "bad quality" from the conversation, refocusing your work on the data and what the data reveals.

How do you measure eCommerce success?

eCommerce is a fast-paced industry. The internet shortened our attention spans and our patience, and everything needs to be solved yesterday. It is natural that eCommerce professionals look for fast fixes and shortcuts to the eternal question: how can I reach eCommerce success with less effort?

For a long time, success was measured with the classic growth formula:

Traffic x conversion rate x average order value = revenue

In the example store above, that is 50,000 sessions x 2% x $80 = $80,000.

That formula was changed by the pandemic, rising customer acquisition costs, the scarcity of third-party data and growing competition. The lifecycle view looks at growth this way:

Number of customers x customer lifetime value / customer acquisition cost

This is not a revenue equation. It is a way of reading growth: grow the customer base, grow what each customer is worth, and keep the cost of winning them under control. If CAC rises faster than CLV, more customers can mean less profit.

As you move from acquisition marketing to lifecycle marketing, metrics related to customer experience help you predict your success. A high NPS, a high repeat customer rate, and strong AOV and CLV should be your priorities. Even if your short-term goals are about traffic, open rates and conversions, that is only half of your job. In the long term, your path to business success depends on the happiness of your customers.

This is the job Nexus by Omniconvert was built for. Nexus connects orders to customers, calculates CLV, retention and churn by segment, and uses RFM segmentation to show which customers are worth the most and which are drifting away. You can then push those segments directly to Meta Ads, Google Ads and Klaviyo. To improve the conversion side of the formula, Omniconvert Explore lets you A/B test the product pages, cart and checkout that drive conversion rate and cart abandonment.

Frequently asked questions about eCommerce metrics