Display ads that load light and perform measurably.

Display advertising rarely fails on design

A banner can look great and still never serve correctly. Too heavy for the publisher’s limits, a missing clickTag, an animation that stutters on an iPhone, or a leaderboard where the price is unreadable. Each of these details costs reach, approval time or measurability. Dometrics therefore builds HTML5 banners starting from the specification: first the technical requirements of every booked placement, then a design that gets its message across clearly within those limits.

What an HTML5 banner has to deliver

HTML5 banners are small web applications. They consist of HTML, CSS, JavaScript and images, are handed to an ad server as a ZIP package and run in an isolated frame on the publisher’s page. Compared with static images, they offer animation, interaction and sharp rendering on every screen density. Compared with video, they are far lighter.

For leadership, one question matters most: is the ad seen, understood and measured? The answer depends on three things. First, a format that fits the placement. Second, a message that works within a few seconds, even without the full animation. Third, click and conversion measurement that runs unbroken from the ad server to the dashboard.

How Dometrics builds banners

A spec matrix before the first draft

It all starts with the media plan. Dometrics collects the specifications of every placement in a spec matrix: dimensions, weight limits, permitted animation length, polite load requirements, click implementation and approval process. Austrian media sales houses such as ORF-Enterprise, Goldbach, IP Österreich, Styria or Russmedia publish their own specifications for special formats. Ad servers like Campaign Manager 360, Google Ad Manager and the systems of other providers have their own requirements for package structure and click tracking. Dometrics delivers the ads in the right form for each of these systems. Checking those rules only after the design is finished means producing everything twice.

Master design and storyboard

One lead format, usually the medium rectangle or the half page, is fully designed and signed off as a storyboard. The end frame is the most important frame: many users only catch a banner out of the corner of their eye or after the animation has finished. Brand, offer and call to action have to make sense there even without the rest of the animation.

Lean engineering

Animation runs on CSS and lean libraries such as GSAP, and graphics are embedded as SVG or compressed WebP. Fonts are subset or, where possible, replaced with system fonts or vector paths. Rich media formats with video or interaction use polite load so the banner doesn’t weigh down the publisher’s page. Every format comes with a static backup image for environments where HTML5 doesn’t execute.

Special formats, rich media and video

On news portals, special formats take up considerably more screen space than standard banners. A sitebar grows with the screen width to the right of the content and stays visible while scrolling. Site branding frames the entire page with a header banner and side panels, and calls for a design that doesn’t cover the editorial content. Sticky ads cling to the edge of the screen, while reveal or understitial formats uncover a visual as the user scrolls. Each of these formats comes with its own rules on background color, close button, frequency and load behavior.

Interactive banners go one step further. A product slider shows several items in one placement, a before/after control makes an effect visible, hotspots explain a product’s details. Video banners combine moving images with a clickable end frame. They usually start muted, so the message has to work without sound. Every interaction is captured as its own event. That adds a metric showing whether a visual earns attention, even when no click follows.

Quality assurance and trafficking

Every package is tested in current browsers and on real mobile devices. Dometrics tests click-through directly in the ad server, checks the weight of every load stage and documents everything in a QA log. Files follow a fixed naming convention so variants stay clearly identifiable in reporting.

Creative for digital out-of-home (DOOH)

Digital screens at bus and tram stops, in train stations, shopping centers or along roads follow their own rules. There’s no click, no sound and usually only a few seconds of attention in passing. The spot runs in a loop with other advertisers and is often seen from several meters away. An upscaled online banner rarely works there.

Dometrics produces DOOH creative to the current spec sheets of each media owner, for example Gewista and Epamedia in Austria or Ströer in Germany. These define screen formats in portrait or landscape, resolution, file format and spot length, as well as whether a visual may be static or animated. On top of that come approval deadlines and content rules that differ by network. All of it goes into the same spec matrix as the online formats. When DOOH is bought programmatically through Display & Video 360, the requirements of the respective inventory apply as well.

The design rules are simple: few words, large type, clear contrast, logo and offer visible from the first frame. Animation stays calm so the visual can be read in passing. Because the DOOH visuals come from the same master design as the HTML5 banners, the campaign looks consistent on the street and online. Performance is assessed through the media owners’ proof-of-play reports and through the development of branded searches and website visits in GA4 in the targeted regions.

Measurement: what a banner achieves

Click-through rate is a weak metric for display. Many impressions work without a click, and accidental taps on mobile distort the picture further. Dometrics therefore evaluates banners on several levels:

• Viewability: Under the MRC standard, a display impression counts as viewable when at least 50 percent of its area is in the viewport for at least one second. It's measured through Active View in Google Ads, DV360 and CM360, and placements with weak viewability are weeded out.
• Interaction rate: For rich media, what counts is how many people use the slider, move the control or start a video.
• Post-view and post-click conversions: via Floodlight in CM360 and DV360 plus server-side tracking on the company's website.
• Cost per conversion by format and variant: which format and which message actually contribute to the result?
• Brand lift studies: for reach campaigns, through Google Ads or DV360, where direct attribution reaches its limits.

The basis for all of this is a clean measurement architecture of the kind built in Tracking & Data Analytics. All figures come together in the Dometrics dashboard, next to search, social and e-commerce, instead of in an isolated ad server report.

Common sources of error

The most frequent problems are matters of craft. Banners are simply scaled down from a social visual, leaving 320×50 with no readable word. Animations end on a frame without a logo or offer. Fonts are embedded in full and blow the weight limit. The clickTag is hardcoded, so clicks bypass the ad server. Online visuals are reused unchanged for DOOH, even though a screen is read from a distance. And variants carry file names like “final_v3_new” that nobody can map in reporting anymore.

How HTML5 banners fit into the Growth Engine

Display ads are the visible end of a longer chain. They’re booked through programmatic advertising in DV360, via the Google Display Network as part of paid advertising, or directly with media sales houses. For large catalogs, dynamic ads take care of filling them with product data. And ideally the click lands on a dedicated landing page whose message matches the banner exactly.

Within the Growth Engine, banners are therefore not a one-off design project but an ad asset that is tested continuously. Every variant produces data, and every iteration builds on the results of the last. If Dometrics sees no sensible role for display in a company’s mix, for example because the audience is reached almost entirely through search or social, it advises against it. The scope of work and ongoing support is outlined on the pricing page.