Display Banners

What it is

Standard IAB sizes — 300x250, 728x90, 160x600, 320x50, 468x60 — served as image or HTML5 creatives. The format every advertiser knows, every publisher has slots for, every panel measures the same way.

I rarely run banner-only campaigns. I use display banner as the control arm for push and in-page push A/B tests, because the format is mature enough that the CTR distribution is stable and the publisher-quality signal is well-calibrated.

Why display matters even if it isn’t your headline format

• Low-variance baseline: 300x250 CTR on Tier-1 EU iGaming ran 0.21–0.34% across Q2–Q3 2024 (n=8.4M, six publisher networks aggregated). The standard deviation across networks is tighter than push by a factor of ~2.3. That tightness is what makes it useful as a control.
• Honest CR-given-click: display CR ran 2.4–3.6% on the same offers. Higher than native (1.1–1.8%) and roughly comparable to push (2.1–3.0%) per click. The total impression volume is the difference — display delivers more, push converts a higher share of the warmed-up audience.
• Smart-CPM behaviour: display is where Smart CPM bidding stabilises fastest. Below 200 conversions you’re letting the bidder overfit on noise regardless of format, but for display the convergence is roughly 30% faster than push in my tests.

When display is the right call

• Always-on brand awareness with predictable spend
• Tier-1 brand budget where the publisher list matters more than the conversion rate
• Retargeting warm audiences with single-creative consistency
• A/B-test control arm against any other format

When it isn’t

• Direct-response on cold audiences — display CTR is too low to feed enough clicks into a CR test
• Mobile-first iOS audiences without Safari banner coverage in the supply
• Verticals (iGaming, adult) where publisher brand-safety filters reject the creative

Specs

• Pricing models: CPM · CPC
• Devices: Mobile + Desktop
• Geo coverage: 240+ countries
• Anti-fraud: Multi-layer filtering + ML scoring on every impression

A note for push advertisers: pairing push with a display retargeting layer lifted my Tier-1 iGaming day-14 CR by 12.8% relative (p=0.03, n=18,200 conversions, Q1 2024). The lift is in the multi-touch, not in either format alone.