10 eCommerce KPIs to Track Monthly (2026 SA Guide)

Revenue is vanity. Profit is sanity.

Most store owners track one number. Revenue.

Wrong number.

Revenue is what comes in the door. It feels like winning. It is not the same as winning.

A store doing R1 million a month at 4% net keeps R40,000. A store doing R400,000 a month at 18% net keeps R72,000. Smaller store. Nearly double the money in the bank.

KPIs are the symptoms. They tell you if the business is healthy or quietly bleeding. Ignore them and you only find out when the bank account does.

So here are the 10 numbers to check every month. Same day, every month. No guessing. No drama.

The 10 ecommerce KPIs to track every month

Here is the full list at a glance. Formula, what it tells you, and the healthy 2026 benchmark to aim for. The detail on each one is below.

KPI	Formula	Healthy 2026 benchmark
Conversion rate	Orders ÷ visitors × 100	2 to 3%+
Average order value (AOV)	Revenue ÷ orders	Higher every quarter
Customer acquisition cost (CAC)	Ad + sales spend ÷ new customers	Well under your LTV
Lifetime value (LTV)	AOV × purchase frequency × lifespan	3x your CAC or more
LTV:CAC ratio	LTV ÷ CAC	3:1 or better
Repeat purchase rate	Returning customers ÷ total customers × 100	20 to 30%+
Gross profit margin	(Revenue − COGS) ÷ revenue × 100	50%+
ROAS	Revenue ÷ ad spend	Above your break-even ROAS
Profit on ad spend (POAS)	Profit ÷ ad spend	Above 1x, and rising
Net profit margin	Net profit ÷ revenue × 100	10 to 20%

Ten numbers. One page. Check them monthly and you will spot a problem while it is still small enough to fix.

1. Conversion rate

Conversion rate is the percentage of visitors who actually buy. It is the purest test of whether your store turns interest into money.

Formula: orders divided by visitors, times 100. If 10,000 people visit and 200 buy, that is a 2% conversion rate.

The global median is around 2%, based on 2025 benchmark data from Triple Whale and Polar Analytics. Top stores push past 3%. Most sit below the median and wonder why.

It swings hard by category and by device. The number you cannot ignore: desktop converts at roughly 3.9%, mobile at just 1.8%. Most of your traffic is on a phone. If your mobile checkout is clunky, you are leaking the majority of your sales. Fix mobile first.

Watch this monthly. A dropping conversion rate is the first sign something broke, before revenue even tells you. We dig into the usual culprits in why your online store conversion rate is dropping.

2. Average order value (AOV)

AOV is the average amount a customer spends per order. Lift it and you make more money without paying for a single extra click.

Formula: total revenue divided by number of orders. R100,000 from 250 orders is an R400 AOV.

This is the cheapest growth lever there is. More traffic costs money. A higher AOV is almost free margin. Across Triple Whale's brands buying paid traffic, the median AOV was about $74 in 2025, but the number that matters is yours, trending up.

Three ways to lift it:

• Bundles. Sell the laptop with the case and the mouse at a small discount.
• Free-shipping threshold. "Free delivery over R750" nudges the R600 cart to add one more item.
• Upsells at checkout. Offer the bigger size, the warranty, the refill pack.

Raise AOV by R80 on every order and the whole business gets healthier overnight. Same ad spend. More margin.

3. Customer acquisition cost (CAC)

CAC is what it costs you to win one new customer. Get this wrong and you can sell hard all month and still go backwards.

Formula: total marketing and sales spend divided by new customers. Spend R30,000 on ads, win 100 customers, your CAC is R300.

Here is the brutal part. According to ecommerce finance firm Eightx, acquisition costs have roughly tripled since 2015, climbing from about $25 to near $80 per customer in many categories. You are buying the same customer for a lot more than you used to.

That is why CAC on its own means nothing. R300 to win a customer is brilliant if that customer is worth R5,000. It is suicide if they are worth R250. CAC only makes sense next to LTV, which is next.

To pull CAC down: kill the ad channels that bring expensive, low-quality buyers and double down on the ones that do not. This is the daily job of a good Meta Ads and Google Ads setup.

4. Lifetime value (LTV)

LTV is the total profit a customer brings you over the whole time they buy from you. It is the most important number in ecommerce, and the one most stores get wrong.

Formula: average order value times how often they buy a year times how many years they stay. R500 AOV, twice a year, for five years, is an LTV of R5,000.

Why it matters: it tells you how much you can afford to spend to win a customer. If a customer is worth R5,000, suddenly an R800 CAC is cheap, not scary.

A high LTV means loyal, repeat buyers. That is where the real money lives. The first order usually just pays for the ad. The second, third, and fourth orders are where profit actually shows up.

We break the full calculation down in our guide on customer lifetime value.

5. The LTV:CAC ratio (the one that pays your bills)

This is the single ratio that tells you if your store has a real business under it. It compares what a customer is worth to what they cost to get.

Formula: LTV divided by CAC. An LTV of R5,000 and a CAC of R1,000 gives you a 5:1 ratio.

The health benchmark is 3:1, according to ecommerce finance specialists like Eightx. For every R1 you spend to win a customer, you want at least R3 back over their lifetime.

It moves by niche. Data from AdZeta puts supplements and health at 3:1 to 6:1, beauty and skincare around 3:1 to 5.5:1, and mid-market apparel at 2:1 to 4:1.

• Under 1:1, you lose money on every customer. Scaling ads just loses it faster.
• Around 3:1, you have a healthy, scalable store.
• Above 5:1, you are likely under-spending. You could grow faster.

If this ratio is healthy, pour fuel on the fire. If it is broken, fix the store before you spend another rand on ads.

6. Repeat purchase rate

Repeat purchase rate is the share of your customers who come back and buy again. It is the cheapest profit in your business.

Formula: returning customers divided by total customers, times 100. 1,000 customers, 300 buy again, that is a 30% repeat rate.

Why it is gold: winning a new customer costs you a full CAC. Selling to an existing one costs almost nothing. They already trust you.

Bain & Company found that lifting customer retention by just 5% can grow profit by 25 to 95%. Not a typo. Retention is a profit strategy, not a nice-to-have.

How to push it up:

• Email and WhatsApp follow-up. A post-purchase flow that thanks them, helps them, then sells the next thing.
• Reorder reminders. If they buy a 30-day product, message them on day 25.
• A simple loyalty perk. A reason to come back to you, not the competitor.

The fastest win for most SA stores is email. Here is how to build and monetise an ecommerce email list, and the deeper reasons behind what drives repeat purchases.

7. Gross profit margin

Gross profit margin is what is left from a sale after you pay for the product itself. It is the foundation every other number sits on.

Formula: revenue minus cost of goods sold, divided by revenue, times 100. Sell for R200, product costs R100, that is a 50% gross margin.

Aim for 50% or higher. That cushion has to absorb ads, shipping, fees, and still leave you a profit. Thin gross margin means there is nothing left to cover the rest.

Here is the trap. Most founders feel rich at 60% gross. Then ads, shipping, and payment fees eat the rest, and net lands at 6%. Gross margin lies. Net margin tells the truth.

We go deep on the targets by niche in our ecommerce profit margins benchmarks guide.

8. ROAS (return on ad spend)

ROAS is how much revenue you get back for every rand spent on ads. It is the number every ad platform shows you first, and it is the most misread number in ecommerce.

Formula: revenue from ads divided by ad spend. R100,000 in sales from R50,000 in ads is a 2x ROAS.

The catch: ROAS only counts revenue, not profit. A 2x ROAS looks fine until you remember the product, shipping, and fees still have to come out of that revenue. On thin margins, a 2x ROAS can lose you money.

So ROAS is only useful next to your break-even ROAS, the point where the ads pay for themselves once product cost is counted. Above it, you profit. Below it, you bleed, no matter how green the dashboard looks.

This is exactly why we do not stop at ROAS. We go one step further, to POAS.

9. Profit on ad spend (POAS)

POAS is profit on ad spend. It is ROAS with the truth switched on. Instead of revenue, it uses actual profit.

Formula: profit divided by ad spend. R100,000 revenue, R50,000 in costs, R25,000 in ads gives R50,000 profit, so a 2x POAS. You made R2 in profit for every R1 of ads.

This is the number we run every client's account on. ROAS can look like a hero while the bank balance bleeds. POAS cannot lie to you, because it already counts the product cost, the shipping, and the fees.

Switch your team from chasing ROAS to chasing POAS and the whole strategy changes. You scale the campaigns that bank money, not the ones that just look good. We break the full difference down in ROAS vs POAS for ecommerce.

10. Net profit margin

Net profit margin is the last word. It is the percentage of revenue you actually keep after every single cost is paid.

Formula: net profit divided by revenue, times 100. R100,000 in revenue and R89,000 in costs leaves R11,000, an 11% net margin.

A healthy ecommerce net margin sits at 10 to 20%, with the best stores running above 18% net according to TrueProfit's analysis of more than 5,000 stores. Under 5% net is fragile. One bad ad month and you are in the red.

This is the number that pays your salary, funds your next push, and decides whether the business survives a quiet quarter. Every other KPI on this list exists to move this one up.

How often should you track ecommerce KPIs?

Not all KPIs move at the same speed. Checking net margin every hour is pointless. So is checking site traffic once a quarter. Match the cadence to the metric.

Cadence	What to check	Why
Daily	Traffic, conversion rate, ROAS/POAS, ad spend	Catch a broken funnel or a runaway campaign fast.
Weekly	AOV, CAC, add-to-cart and cart abandonment	Spot trends early enough to act on them.
Monthly	LTV, LTV:CAC, repeat rate, gross and net margin	The strategic picture. The numbers that decide direction.

Personally, I review the full set every 14 days. Frequent enough to make quick adjustments, not so often that I drown in noise. That rhythm is the difference between just getting by and pulling ahead.

If you only ever track one, track net profit margin. If you want a slightly different lens, here is the case for the number one metric to grow your store profitably.

What changes for South African store owners

The global benchmarks above are a good map. But SA stores carry costs the international numbers ignore. Build these in before you call your store healthy.

• VAT at 15%. Work out your margins on the price excluding VAT, not the sticker price. Get this wrong and you overstate every margin you have. From 1 April 2026 the compulsory VAT registration threshold rose to R2.3 million in any 12 months, up from R1 million, so price for VAT before you cross that line.
• Payment gateway fees. Local gateways like PayFast, Yoco, and Peach take roughly 3 to 3.5% per sale plus a small fixed fee. On a 12% net margin, that is a real bite out of every order.
• Courier and last-mile. Getting the box to the customer is a serious line item here, especially outside the big metros. It is not free, and it is not small.
• Rising ad costs. Meta's own reporting shows ad costs up double digits year on year through 2025. You are handing Zuckerberg more of your wallet for the same click you bought cheaper last year. This is exactly why we measure POAS, not just ROAS.

Your practical target as an SA store: protect a gross margin of 55% or higher. That cushion absorbs VAT, fees, courier, and rising ad costs, and still lands you at a healthy 10 to 15% net.

Frequently asked questions