CTR & CPM.
aka click-through rate, cost per mille, cost per thousand impressions
Did they click, and what did it cost to be seen? The two numbers every ad runs on.
What it actually means
CTR (click-through rate) is the percentage of people who saw an ad or link and clicked it. CPM (cost per mille) is what an advertiser pays for every thousand times the ad is shown. Together they tell you how expensive attention is and how well your ad turns attention into action.
CTR maths: clicks divided by impressions. 50 clicks on 10,000 impressions is a 0.5% CTR. CPM maths: cost divided by impressions, times 1,000. Spend $40 to be shown 10,000 times and your CPM is $4. Multiply them and you get cost per click: $40 for 50 clicks is $0.80 each.
They move independently. CPM depends on the market (how many advertisers want that audience on that platform at that time; it spikes before Black Friday). CTR depends on you (the creative, the headline, the match between ad and audience). The common mistake is chasing a low CPM: cheap impressions shown to people who never click are not a bargain.
Where you'll hear it
CPMs went from $6 to $11 this week because of the holiday auction, but our CTR held at 1.4%, so cost per click only rose 30%. The new creative is carrying it.
Translation: the platform got more expensive for everyone, and the ad is good enough to soften the blow.
You will hear both in any ad-buying conversation, media plans, influencer pricing (creators sometimes quote a CPM for sponsored posts) and in publishing, where CPM is also the rate a website earns per thousand ad views. Same acronym, other side of the deal.
The pop-culture version
A billboard company charges you per thousand people who drive past it. That is CPM: you pay for being seen, whether anyone cares or not. A billboard on a motorway costs more per thousand than one on a side road, because more brands want that spot.
Now count how many of those drivers actually pull over and come in. That ratio is CTR. A billboard with a confusing message on the best road in town gets a big audience and no visitors. A sharp, funny one on a quieter road might win.
Online ads are the same billboard, rented by the thousand views and judged by who walks in.
This is also how sites like kurums.com earn money from ads: advertisers bid for impressions (CPM) and clicks, and the site gets a share. The publisher side calls its version RPM, revenue per thousand pageviews.
Say it like you mean it
“CPM is $8, CTR is 1.2%, so we’re paying about 67 cents a click.”
Shows you know how the two combine into the number finance actually cares about.“Our CPM is great, it’s only $2.”
Cheap impressions with a 0.1% CTR cost $2 a click. Low CPM alone says nothing about whether the ad works.The rule of thumb: CPM is the price of the room, CTR is how good your pitch is. You negotiate or wait out the first, and you improve the second with better creative and targeting.
The Kurums digital-ads pillar: how auctions price attention, how to read ad metrics together and how to work out break-even spend.
Decoded next
Decoded by the Kurums editorial team. Kurums Decoded translates the language of business for people who are new to it. Definitions are kept short on purpose; the serious version above goes deep. Nothing here is financial, legal or career advice.
Discover more from Kurums | Business Intelligence
Subscribe to get the latest posts sent to your email.
