Developer Advertising

Google display ad sizes

300 × 250 6:5

Max 150.0 KB ·JPG or PNG

The single highest-inventory size.

300 × 250

Drop an image to check it Optional — the spec is above either way. Nothing is uploaded.

Cropped in your browser · your image is never uploaded

Local · 150 KB cap on every size

Five sizes cover the overwhelming majority of display inventory: 300 × 250, 728 × 90, 160 × 600, 320 × 50 and 300 × 600. All are capped at 150 KB.

How to use the google display ad sizes

1 Read the dimensions above. That is the whole answer if the spec is all you came for.

2 Drop your own image in to check it against the spec — size, aspect ratio and file weight are each checked separately.

3 Turn on the safe zone to see what gets cropped or covered, then download the cropped version at the exact size.

Google supports a long list of sizes but the distribution is heavily skewed, and building all of them is a poor use of time. The medium rectangle at 300 × 250 alone takes a large share because it fits both desktop sidebars and in-article mobile slots. If you build only two, build that and the 320 × 50 mobile banner, since mobile is where most impressions are. The 150 KB cap is the other practical constraint — it rules out photographic backgrounds at these dimensions and pushes designs toward flat colour and type, which is why display advertising looks the way it does.

Questions

Which display ad sizes should I make first? −

300 × 250 and 320 × 50. Between them they cover most inventory across desktop and mobile.

What is the file size limit? +

Why is 300 × 250 so dominant? +

Do I need every size? +

Should I use JPEG or PNG? +

Sources

Google Ads Help — display ad specifications

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