Position affects an ad's performance more than the creative does. A mediocre banner high on the page beats an excellent one nobody scrolls to.
The positions that work
Immediately below the header, above the content. The most-seen position on almost every site. Visible without scrolling on most screens. Best viewability, best click rate, and what you should charge most for.
Mid-content, after two or three paragraphs. Strong on both desktop and mobile, because a reader who has got that far is engaged. Often outperforms the sidebar on click rate.
Sidebar, top. Good on desktop, near-worthless on mobile — sidebars usually reflow to below all the content, where almost nobody reaches. If your traffic is mostly mobile, treat this as a desktop-only slot and price accordingly.
End of article. Modest impressions but qualified ones. A reader who finished is receptive. Works especially well for text and native placements.
The positions that do not
Footer. Almost never seen. Occasionally worth including free as a bonus, never worth selling alone.
Sidebar, low. Below the fold on desktop and below everything on mobile.
Anything below three stacked units. Each unit in a column is seen less than the one above it. By the third, viewability is usually under 20%.
Check your own split first
Before deciding anything, look at what share of your traffic is mobile. For most independent publishers it is 55–75%.
If two-thirds of your readers are on a phone, a desktop sidebar slot reaches a third of your audience at best. That should change both where you put ads and what you charge for each position.
Let the data decide
Rather than arguing about it, measure. For each placement, track:
- Viewable rate — what share of served impressions were actually seen
- Click-through rate — clicks divided by impressions
- Fill rate — how often something was available to show
Run for a month. You will usually find one position doing two or three times the click rate of another, and that tells you which one to sell as premium.
A layout that works for a typical article site
- Leaderboard below the header — 728×90 desktop, 320×50 mobile. Premium slot.
- In-content after paragraph three — 300×250, responsive. Second premium.
- Sidebar top — 300×250, desktop only, priced lower.
- End of article — text or native, sold as a package with anything above.
Four slots is plenty. Beyond that, each additional unit cannibalises the ones above and pushes more readers to install a blocker.
Two things that quietly cost you
Layout shift. An ad that loads and pushes content down is the single most irritating thing advertising does. Reserve the space with fixed dimensions so the slot occupies its area before the ad arrives.
Stacking on mobile. Two ad units within one screen height reads as spam. On mobile, keep at least a full screen of content between units.