Ecommerce KPIs: The 10 Metrics That Show Whether Your Store Is Actually Healthy

The ecommerce KPIs that matter most are conversion rate, email signup rate, average order value, customer acquisition cost, break-even ROAS, first-to-second purchase rate, time between orders, repeat revenue percentage, customer lifetime value by cohort and contribution margin after marketing. Together they answer three questions: are you turning traffic into buyers, are buyers coming back, and is your growth actually profitable? Track them as one set, against your own numbers over time.

Most ecommerce dashboards are full of numbers.

Sessions. Bounce rate. Followers. Open rate. Revenue.

Very few of them tell you whether the business is getting stronger.

Here's a quick test. If your ads stopped tomorrow, would your revenue collapse? For most ecommerce brands, the honest answer is yes. The 10 KPIs below show you why, and where to fix it.

By Emiel Dingemans, Founder of Magicianly

Updated October 2026

What Is an Ecommerce KPI?

An ecommerce KPI (key performance indicator) is a number you track because it tells you whether your store is moving toward its goals.

Every KPI is a metric. Not every metric is a KPI.

Sessions, open rate and page views are metrics. They help you diagnose a problem. A KPI tells you whether there is a problem in the first place: are you getting buyers, are they coming back, and are you keeping enough of every sale?

Which Ecommerce KPIs Should You Track?

These are the 10 we look at first when we open an ecommerce account:

They fall into three groups: turning traffic into buyers, bringing buyers back, and making sure the whole thing is profitable.

Which KPIs Show Whether You're Turning Traffic Into Buyers?

1. Conversion rate

Conversion rate = orders ÷ sessions × 100

In a lot of the stores we look at, around 2 out of every 100 visitors buy. The other 98 leave.

That's not a reason to panic. It's a reason to look at what happens to those 98 people. Read your conversion rate by traffic source and by device, because one blended number hides where the problem is. And don't try to buy a higher conversion rate with bigger discounts. That just moves the problem to your margin.

2. Email signup rate

Signup rate = new popup subscribers ÷ visitors × 100

Most of the visitors you paid for won't buy on their first visit. Your signup rate tells you how many of them you can still reach.

In most accounts we open, the popup converts around 2 to 3% of visitors. With a better offer and a question before the email field, we regularly get brands to 8 to 12%. Here's what a good popup signup rate looks like and how to raise it.

3. Average order value

AOV = total revenue ÷ number of orders

AOV tells you how much each order brings in. A higher AOV means every visitor you paid for is worth more, as long as you didn't get there with discounts. Here's how to raise your average order value without discounting.

4. Customer acquisition cost

CAC = total marketing spend ÷ number of new customers

For example, $40,000 in marketing spend and 800 new customers gives you a CAC of $50.

Use blended CAC, across all your channels, not the cost per purchase your ad platform reports. Here's how to calculate customer acquisition cost properly.

5. Break-even ROAS

Break-even ROAS = 1 ÷ contribution margin ratio (before ad spend)

If an order leaves you 55% after product, shipping and payment costs, your break-even ROAS is 1 ÷ 0.55 = 1.82. Below that, every sale from your ads loses money on the first order. Here's how to calculate your break-even ROAS and why retention lowers it.

Which KPIs Show Whether Customers Come Back?

6. First-to-second purchase rate

First-to-second purchase rate = first-time buyers who order again ÷ all first-time buyers in the same period × 100

This is the KPI we watch most closely. The first purchase is hard to get. The second purchase is where the profit starts.

Always use a fixed window, like 90 days after the first order, so you compare cohorts fairly. Here's how to read your repeat purchase rate and why first-to-second is often the more useful number.

7. Time between orders

Time between orders tells you how long customers take to come back. For a lot of brands, the second order comes within weeks, not months.

That matters because it tells you when your post-purchase emails need to land. Here's how to calculate the average time between orders for your store.

8. Repeat revenue percentage

Repeat revenue percentage = revenue from returning customers ÷ total revenue × 100

If your repeat revenue is low, you're renting your growth from your ads. Every month, you have to buy it again.

Read it next to how fast you're acquiring new customers. A brand that's scaling acquisition quickly can see this number drop while retention is actually fine, because new customers are coming in faster than the repeat base can catch up.

9. Customer lifetime value by cohort

30-day cohort LTV = revenue from a cohort's orders within 30 days of each customer's first order ÷ number of new customers in the cohort

A cohort is everyone who placed their first order in the same month. Do the same at 60 and 90 days.

One blended lifetime value number mixes customers from three years ago with customers from last week. Cohorts show you whether newer customers are becoming more valuable. Here's how we measure customer lifetime value by cohort.

Which KPI Shows Whether Your Growth Is Profitable?

10. Contribution margin after marketing

Contribution margin after marketing = revenue minus variable costs minus marketing spend

For example, a $100 order with $45 in product, shipping and payment costs and $25 in marketing leaves you $30, or 30%.

If I could only track one ecommerce KPI, it would be this one. Revenue tells you how much you sold. Contribution margin after marketing tells you how much you kept. Revenue can grow while this number shrinks, and when that happens, you're scaling inefficiently. Here's how to calculate contribution margin step by step.

How Do These Ecommerce KPIs Work Together?

No single KPI tells you whether your store is healthy. They work as a chain:

1. 1A shorter time between orders improves your 30-day LTV.
2. 2A higher first-to-second purchase rate increases your repeat revenue percentage.
3. 3More repeat revenue takes pressure off your blended CAC.
4. 4A lower blended CAC improves your contribution margin after marketing.

That's also why we read them in pairs. These are the combinations that tell us the most:

• Revenue is growing, but contribution margin after marketing is shrinking: you're scaling inefficiently.
• Blended CAC is rising and repeat revenue percentage is flat: retention isn't offsetting your acquisition costs.
• First-to-second purchase rate is low and 30-day LTV is weak: your retention system is probably broken.
• Email revenue is growing, but contribution margin isn't improving: you're probably too discount heavy.

Which Ecommerce Metrics Are Not KPIs?

Open rate, click rate, sessions, followers and platform-attributed revenue are useful, but they're diagnostics.

A campaign can get a great click rate by sending people to a discount they didn't need. A flow can get a lot of attributed revenue from people who were going to buy anyway. Neither tells you whether the business got stronger.

Use them to find out why a KPI moved, not as the goal. For the email side, here are the email marketing metrics we use and how they connect.

How Often Should You Check Your Ecommerce KPIs?

You don't need a complicated dashboard. One page with these 10 numbers, compared with last month and the same month last year, is enough for most brands.

The weekly numbers move fast and tell you if something broke. The monthly and quarterly numbers move slowly and tell you if the business is getting stronger.

What Are Good Benchmarks for Ecommerce KPIs?

For most of these KPIs, there's no universal good number.

A brand selling a consumable product will have a very different repurchase rate and time between orders than a brand selling something people keep for years. Your margin, price point and whether you offer subscriptions all change what "good" looks like.

So compare each KPI with your own history, and compare newer cohorts with older ones. The direction matters more than someone else's average.

So Which Ecommerce KPIs Should You Track?

• Track 10 KPIs in three groups: traffic into buyers, buyers coming back, and profit.
• Traffic into buyers: conversion rate, email signup rate, average order value, customer acquisition cost and break-even ROAS.
• Buyers coming back: first-to-second purchase rate, time between orders, repeat revenue percentage and customer lifetime value by cohort.
• Profit: contribution margin after marketing, the one number we'd judge a store by.
• Read them in pairs, and treat open rate, click rate and attributed revenue as diagnostics, not KPIs.
• Compare every KPI with your own numbers over time, not with another brand's.

Revenue shows how big your store is. These 10 KPIs show whether it's getting stronger.