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HomeBanner sizes › 300×250

Make a 300×250 medium rectangle ad

The most widely bought display unit there is. Nearly square, sits inside article content, and carries the broadest inventory on the Google Display Network. If you only build one size, build this one.

A live 300×250 ad, cutting between three frames

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The specification

Dimensions300 × 250 pixels
Aspect ratio1.2:1
Common nameMedium Rectangle (MPU)
CategoryDisplay advertising
Where it runsInside or directly below article content, and in sidebars. Desktop and mobile both serve it, which is why it wins the most impressions of any single unit.
Export formatsHTML5 banner package for ad servers, animated GIF for display networks, or static PNG and JPG.

Designing for this shape

It is almost square, so stack it

At 6:5 you have real vertical room. A headline of two short lines, a supporting line, and a proper call-to-action button all fit without crowding.

Keep the button a button

There is space for a CTA around 36 to 44 pixels tall. Make it look pressable, with solid fill and a clear label. Do not shrink it to fit more words in.

Three or four words a line

Anything longer and the type has to drop below comfortable reading size for a unit this small.

Frames and timing

Three frames suits it: a hook, one benefit, then the call to action. Hold the closing frame longest, because that is the one people act on.

The trap: Designers often reuse a social square here. The proportions look close but 300x250 is much smaller on screen, so type that reads fine at 1080x1080 becomes unreadable.

File weight

The Google Display Network sets a maximum of 150 KB per creative, applied to both image and HTML5 units. Many networks also cap animation length, commonly at 30 seconds, and require the loop to stop after a small number of repeats.

Every network and placement enforces its own specification, and those change. Confirm the current maximum file size, animation length and format support for the platform you are running on before you publish.

Sizes that pair with it

A campaign is rarely one size. These are the units most often bought alongside 300×250, and one design can be fitted across the whole set with shared margins and synced headlines.

See the full banner size guide for every standard dimension, or read about how frame animation works and GIF weight limits.

Questions

What is a 300x250 ad called?

It is the medium rectangle, often shortened to MPU, which stands for mid-page unit. All three names refer to the same 300 by 250 pixel placement.

Is 300x250 still the best banner size?

It still carries the widest inventory of any single display unit, so it remains the usual first choice. Pairing it with 728x90 and 160x600 covers most desktop and mobile placements.

What file size should a 300x250 ad be?

The Google Display Network sets a maximum of 150 KB. Confirm the limit for the network you are running on, as specifications vary and change.

Open the editor to build a 300×250 ad now, or return to the home page.