The formulas
| Metric | Formula | What it measures |
|---|---|---|
| CPM | spend ÷ impressions × 1000 | Price of reaching the audience |
| CTR | clicks ÷ impressions | How compelling the ad is |
| CPC | spend ÷ clicks | Cost of one visitor |
| Cost per result | spend ÷ results | The bottom line |
| Conversion rate | results ÷ clicks | What happens after the click |
How to diagnose problems with these numbers
Cost per result = CPM ÷ (1000 × CTR × conversion rate). So any increase comes from one of three places:
- CPM went up: more competition, a narrow audience, or low ad quality. Read Facebook Ads High CPM: The Real Causes and What You Can Do.
- CTR went down: the ad stopped grabbing attention, often from fatigue or high frequency. Read Low CTR on Facebook Ads? 8 Causes and How to Raise It.
- Conversion rate dropped: the problem is the landing page, offer or price, not the ad.
Rough benchmarks
Numbers vary a lot by country, industry and season, so compare your account with itself over time first. Roughly speaking in Middle East markets, a link CTR between 0.8% and 2% is normal, below 0.5% is a sign to review the creative, and CPM rises noticeably during Ramadan and at year end.
Use "link clicks", not "all clicks". All clicks include taps on the image, the page name and comments, which inflates CTR.
FAQ
How do I calculate CPM?
Divide the amount spent by impressions and multiply by 1,000. For example 5,000 ÷ 250,000 × 1,000 = 20.
What is a good CTR on Facebook?
Usually 1% to 2% for link clicks, but the trend matters more: a falling CTR on the same ad over time is a sign of ad fatigue.
Does a low CPC mean a successful ad?
Not always. Cheap clicks that don't buy raise your real cost. Judge by cost per result and conversion rate together.