Goals & KPIs (CTR, CPC, CPA, ROAS)
Set SMART goals, then track the right numbers — CTR, CPC, CPA, ROAS and CAC — to know if you are winning.
What you will learn
- Write a SMART marketing goal
- Define the core metrics CTR, CPC, CPA, ROAS and CAC
- Calculate each metric from real numbers
A goal you can actually check
A goal like “get more sales” is too vague — you can never tell if you hit it. Good marketers use SMART goals: Specific, Measurable, Achievable, Relevant, and Time-bound.
- Vague: “get more website visitors.”
- SMART: “get 2,000 website visitors from Instagram in June.”
The SMART version names a number (2,000), a source (Instagram), and a deadline (June). Now you will know if you succeeded.
KPIs — the numbers that matter
A KPI (Key Performance Indicator) is a number you track to measure success. These five are the ones every digital marketer must know.
| Metric | Full name | What it tells you |
|---|---|---|
| CTR | Click-Through Rate | How many who saw the ad clicked it |
| CPC | Cost Per Click | How much you pay for one click |
| CPA | Cost Per Acquisition | How much you pay for one sale or sign-up |
| ROAS | Return On Ad Spend | Revenue earned for every rupee spent |
| CAC | Customer Acquisition Cost | Total cost to win one new customer |
Calculating each one
Let us use one bakery Instagram ad. It was seen 10,000 times, got 500 clicks, cost ₹2,000, and led to 25 cake orders worth ₹10,000 in total sales.
CTR = clicks / impressions = 500 / 10000 = 5%
CPC = cost / clicks = 2000 / 500 = Rs 4 per click
CPA = cost / orders = 2000 / 25 = Rs 80 per order
ROAS = revenue / cost = 10000 / 2000 = 5x (Rs 5 back per Rs 1)Note: Read these together and the ad looks great: a 5% CTR is strong, each order cost only Rs 80, and every Rs 1 spent returned Rs 5 (ROAS of 5x). CAC is like CPA but counts every cost to win a customer, not just ad spend — so it is usually a bit higher.
CAC vs CPA — the small difference
CPA usually counts only the ad cost per sale. CAC counts everything — ads, tools, staff time — to win one new customer. CAC gives the fuller, more honest picture of what a customer truly costs.
Tip: The two numbers a business owner cares about most are ROAS (am I making money on ads?) and CAC (what does each customer cost me?). If ROAS is above 1x you are earning more than you spend — the higher, the better.
Watch out: A high CTR alone does not mean success. Lots of clicks but no orders means you are paying for visits that do not buy. Always follow the chain all the way down to CPA and ROAS, not just clicks.
Q. An ad got 1,000 clicks from 50,000 impressions. What is its CTR?
✍️ Practice
- An ad cost ₹3,000, got 600 clicks and 30 sales. Calculate its CPC and CPA.
- Rewrite this vague goal as a SMART goal: "get more followers on Instagram".
🏠 Homework
- An ad spent ₹5,000 and brought ₹20,000 in sales. Calculate the ROAS and write one sentence on whether the ad was worth it.