What are HTML5 banners?
An HTML5 banner is an online ad built with HTML, CSS and JavaScript, instead of as an image or a separate video. That lets it move without stuttering, respond to a click or a swipe, and show prices or offers from a feed. It stays sharp on every screen. Almost every ad platform plays it, from Google Ads to DV360, Xandr and Adform.
What an HTML5 banner can do, and an image can’t.
An image does one thing: sit there. A gif plays a few frames and starts over, in a limited colour range. An HTML5 banner is a small program. Every layer moves on its own: the product, the headline, the button. That lets the animation run to the second, while the file stays light.
| Static (jpg/png) | Gif | HTML5 | |
|---|---|---|---|
| Movement | none | limited, jerky | smooth, per layer |
| Interaction | click only | click only | swipe, slide, choose, fill in |
| Data from a feed | no | no | yes: price, stock, location |
| Sharpness | fixed size | fixed size | sharp on every screen |
| File size | small | gets heavy fast | small, if it’s built well |
You can click, slide and choose in it.
Because it’s code, the banner can ask something. With ENGIE you answer three questions in the banner itself, and you land on the landing page that matches your answers. Anyone who answers is already engaged. With BridgeFund you choose the amount of your loan with a slider. The banner waits until you do something.
Where the limit is: file size and specs.
Every platform and every publisher has its own specs for file size, loading behaviour and click area, and they vary a lot. Google Ads, for example, takes a zip of up to 600 KB and no more than 40 files (opens in a new window). An HTML5 banner that’s too heavy gets rejected or loads too late. That’s why we check the set against the specs in the media plan up front, and replace heavy images with code wherever we can.
When do you choose HTML5?
Almost always, for display. A static banner only makes sense if the platform allows nothing else, or if the message really fits in one image. If you want someone to do something in the banner (choose, calculate, swipe), HTML5 is the only option.