A banner is measured in pixels, width by height: 300×250 is a banner 300 pixels wide and 250 pixels tall. The sizes that almost every platform uses are called IAB sizes, because that association published them as a standard. Knowing them saves you from ordering pieces nobody can run.
Why there are so many sizes
Each size fits a different type of space: a wide top bar, a tall side column, a rectangle inside the text, a fixed strip on mobile. Whoever buys the space chooses the sizes based on where they want to appear, so a campaign almost never uses just one.
The 14 standard sizes
| Size | IAB name | Shape | Typical use |
|---|---|---|---|
| 300×250 | Medium Rectangle | Rectangle | Inside content and in side columns |
| 336×280 | Large Rectangle | Rectangle | Inside content, a bit larger |
| 728×90 | Leaderboard | Horizontal | Top of the page on desktop |
| 970×90 | Large Leaderboard | Horizontal | Top of the page, full width |
| 970×250 | Billboard | Horizontal | Top of the page, high impact |
| 468×60 | Full Banner | Horizontal | Classic format, less common today |
| 160×600 | Wide Skyscraper | Vertical | Side columns |
| 120×600 | Skyscraper | Vertical | Narrow side columns |
| 300×600 | Half Page | Vertical | Side columns, high impact |
| 320×50 | Mobile Leaderboard | Horizontal | Fixed strip on mobile |
| 320×100 | Large Mobile Banner | Horizontal | Fixed strip on mobile, taller |
| 250×250 | Square | Square | Inside content and side columns |
| 200×200 | Small Square | Square | Small spaces |
| 580×400 | Netboard | Rectangle | Inside content, large format |
In BannerMotion you can choose these 14 sizes (or your own, written as 300x250), and a concept supports up to 12 sizes in total.
Which ones to produce first
If you have to start somewhere, a reasonable selection is 300×250, 728×90, 160×600, and 320×50: a rectangle, a horizontal bar, a vertical column, and a mobile strip. Those four cover the four most common types of space. It is also the selection BannerMotion leaves checked when you create a new banner.
Then expand based on the media buy: if there is budget for large formats, add 300×600 and 970×250; if your traffic is mostly mobile, 320×100.
One idea, many formats
Scaling a design is not the same as adapting it. If you stretch a 300×250 banner to 728×90, the headline ends up tiny and there is wasted space. Adapting means deciding again what goes where: in a horizontal bar, the image usually goes to one side and the button to the right; in a vertical column, everything stacks.
- Start with the hardest size (usually the smallest or most extreme one): if the message fits there, it fits the others.
- Keep the same elements in every size: logo, headline, button.
- Rearrange them for each shape instead of shrinking them all.
- Review each size separately, with the longest text in your language.
Text and button at small sizes
At 320×50 or 468×60 there is almost no room: a short headline, the logo, and a button. Simple rules: one message per banner, text that reads easily at actual size, and a button with enough area to tap on mobile. If it does not fit, the problem is usually the message (too long), not the size.
Weight by size
Each piece has its own weight limit. The large sizes (970×250, 300×600) tend to weigh more because they carry larger images, and on retina screens the weight doubles if you use images at double resolution. Measure each .zip separately, not the set.
Beyond the standard banner
Besides the fixed sizes there are formats that behave differently. Rich media includes ads with interaction or video; expandables grow over the page when someone interacts; interstitials take up the whole screen between two pieces of content. They require support from both the site and the platform, usually weigh more, and have their own rules: confirm them before producing them.
Verified on: [date pending]. The sizes in the table are the ones published by the IAB; the names in English are the official ones.