CPM (cost per mille) is the cost of one thousand ad impressions — what you pay for visibility rather than clicks. A €12 CPM means every 1,000 times your ad renders costs €12. Social and display platforms ultimately bill most campaigns on CPM mechanics, whatever bidding mode you choose.
CPM is the native currency of attention-based channels. Meta, TikTok, programmatic display, and YouTube auction impressions; even when you optimize for clicks or conversions, the platform is internally clearing an impression auction and your effective CPM is what you truly paid for reach. That makes CPM the cleanest lens for two questions: how expensive is this audience, and is my creative earning its keep?
Formula: spend ÷ impressions × 1,000. Reverse it to budget reach: 500,000 impressions at a €9 CPM costs €4,500.
Typical ranges (broad, 2024–2026): Meta feed €5–15, with narrow audiences, Q4 retail competition, and retargeting pools pushing higher; programmatic display €1–4 on open exchanges; YouTube in-stream €4–12; TikTok often €3–8; LinkedIn €25–60 — professional targeting is the most expensive mainstream inventory. Q4 CPMs on retail-adjacent audiences commonly run 30–60% above spring on the same targeting.
CPM connects to performance through CTR: effective CPC = CPM ÷ (CTR × 10). A €10 CPM with 1% CTR is a €1 click; double the CTR and the click costs €0.50 — which is why creative improvement is the main CPM-side lever. Rising CPM on a stable audience usually signals ad fatigue (the platform charges more to force-feed a tired creative) or seasonal auction pressure.
When to actually bid CPM: brand awareness and reach objectives, guaranteed placements, and frequency-controlled campaigns. For direct response, bid conversions and read CPM as a diagnostic, not a target.
Meta campaign: €1,800 spend, 240,000 impressions → CPM = 1,800 ÷ 240 = €7.50. With a 1.2% CTR, effective CPC = 7.50 ÷ 12 = €0.63 per click.
Neither — they price different things. CPC suits intent channels where the click is the product (search). CPM suits attention channels (social, display, video). On Meta you typically optimize for conversions while monitoring CPM as the cost-of-audience diagnostic.
Most often: creative fatigue (engagement drops, so the auction charges more), seasonal competition (Q4), narrowing audiences, or frequency creeping up on a small retargeting pool. New creative and broader audiences are the usual fixes.