Why & WhatCore· 35 min read

Key Marketing Metrics

Five numbers — traffic, conversion rate, CAC, LTV and ROAS — tell you almost everything about whether your marketing is healthy.

What you will learn

  • Define the five core marketing metrics
  • Calculate each one from simple numbers
  • Read a metric and say if it is good or bad

Five numbers every marketer should know

You do not need fifty metrics. Most decisions come down to five. We will use one running example: an online clothing store in India, and work each number out step by step.

1. Traffic

Traffic is simply how many people visited your website or shop. It is the top of the funnel — no visitors, no sales. We measure it as visits over a time period.

Example: the clothing store had 10,000 website visits in May. That is its traffic for the month.

2. Conversion rate

A conversion is when a visitor does the thing you want — usually a purchase. Conversion rate is the percentage of visitors who convert.

Conversion rate for the clothing store in May
Conversion rate = conversions / visitors x 100

= 200 orders / 10,000 visits x 100
= 2%

Note: Out of 10,000 visitors, 200 bought something. That is a 2% conversion rate — a typical, healthy number for online retail. If it were 0.2%, something would be scaring buyers away.

3. CAC — Customer Acquisition Cost

CAC is how much you spend on marketing to win one new customer. Lower is better.

Customer Acquisition Cost (CAC)
CAC = marketing spend / new customers

= ₹50,000 spent / 200 new customers
= ₹250 per customer

Note: The store spent ₹50,000 on ads and gained 200 customers, so each new customer cost ₹250 to acquire. Whether that is good depends on how much each customer is worth — which is the next number.

4. LTV — Lifetime Value

LTV (lifetime value) is how much money one customer brings you over the whole time they stay with you — not just the first order.

Lifetime Value (LTV) of one customer
LTV = average order value x orders per year x years stay

= ₹800 per order x 3 orders a year x 2 years
= ₹4,800

Note: A typical customer spends ₹800 per order, buys 3 times a year, and stays about 2 years. So one customer is worth ₹4,800 over their lifetime. Compare that to the ₹250 CAC — you pay ₹250 to earn ₹4,800. That is a strong, profitable business.

5. ROAS — Return On Ad Spend

ROAS tells you how many rupees of sales you get back for every rupee spent on ads. It is written as a ratio.

Return On Ad Spend (ROAS)
ROAS = revenue from ads / ad spend

= ₹2,00,000 sales / ₹50,000 spent
= 4x  (four rupees back for every rupee spent)

Note: The ads brought ₹2,00,000 in sales from ₹50,000 spent, a ROAS of 4x. A ROAS above 1x means the ads earn more than they cost. Most businesses aim for 3x to 4x or higher to cover other costs and still profit.

The five at a glance

MetricQuestion it answersGood direction
TrafficHow many people came?Higher
Conversion rateHow many of them acted?Higher
CACWhat did one customer cost?Lower
LTVWhat is one customer worth?Higher
ROASRupees earned per rupee spent?Higher

Reading all five together

The skill is not just calculating each number — it is reading them as one story. Here is the verdict for our clothing store in May:

All five metrics read together as one verdict
Traffic:         10,000 visits   -> healthy top of funnel
Conversion rate: 2%              -> normal for online retail
CAC:             ₹250 per buyer  -> cheap to acquire
LTV:             ₹4,800 per buyer -> each buyer is very valuable
ROAS:            4x              -> ads earn 4 rupees per 1 spent

Verdict: HEALTHY. Spend more on ads — the maths supports growth.

Note: No single number tells the story. Traffic is fine, conversion is normal, and the money side is strong: you pay ₹250 to win a customer worth ₹4,800, while ads return 4x. Because LTV hugely beats CAC and ROAS is above target, the safe move is to spend MORE, not less.

Tip: The golden rule: your LTV should be comfortably bigger than your CAC. A common target is LTV at least 3 times CAC. Here it is ₹4,800 vs ₹250 — nearly 19 times, which is excellent.

Watch out: Never look at CAC alone. A ₹250 CAC sounds expensive for a ₹300 product but is a bargain for a customer worth ₹4,800. Always pair CAC with LTV.

Q. A gym spends ₹40,000 on ads and signs up 100 new members. What is its CAC?

Answer: CAC = spend / new customers = ₹40,000 / 100 = ₹400 per member.

✍️ Practice

  1. A bakery website got 5,000 visits and 150 orders. Calculate its conversion rate.
  2. A customer spends ₹500 per order, orders 4 times a year, and stays 3 years. Calculate their LTV.

🏠 Homework

  1. Pick an imaginary shop. Make up sensible numbers and calculate all five metrics for one month. Write one sentence saying if the business looks healthy.
Want to learn this with a mentor?

CodingClave runs guided, project-based training (28-day, 45-day & 6-month batches).

Explore Training →