Online Tool Store
· 4 min read
A Reference for Standard Ad Banner Sizes
Heshan Fernando
Co-founder & COO
You’re designing a display ad, a social media banner, or a promotional graphic, and you need the exact pixel dimensions for a specific ad slot — a leaderboard, a medium rectangle, a mobile banner, a specific social platform’s cover image size. Standard ad and banner sizes exist precisely because ad networks and platforms need consistent dimensions to slot creative into predefined spaces, but there are enough different standard sizes across desktop, mobile, and various social platforms that remembering them all isn’t realistic.
Guessing at dimensions, or working from a half-remembered size, risks a design that either gets rejected by an ad network’s requirements or displays awkwardly cropped or stretched once it’s actually placed.
What standard ad banner sizes actually cover
Display advertising has a set of long-established standard sizes — the leaderboard (728×90), the medium rectangle (300×250), the wide skyscraper (160×600), and others — that ad networks and publishers have converged on as common, interchangeable slot dimensions. Mobile banner sizes form their own distinct set, generally smaller and often with different aspect ratios suited to phone screens. Social media platforms each have their own specific image size requirements for cover photos, post images, and ad formats, which are separate again from traditional display advertising standards and tend to change somewhat as platforms update their interfaces.
Working from a proper reference means you’re designing to an actual established standard from the start, rather than guessing at dimensions and discovering a mismatch only after submitting creative to an ad network or platform.
Why people get stuck here
- There are genuinely a lot of standard sizes to track. Between display ad formats, mobile-specific sizes, and each social platform’s own requirements, no one reasonably has every dimension memorized.
- Different contexts need different, non-interchangeable sizes. A size that works for one ad slot or platform won’t necessarily fit another, even within the same general category.
- Sizes for social platforms change periodically. Unlike traditional display ad standards, which have been stable for a long time, social platform image requirements can shift as platforms redesign their interfaces.
- Guessing dimensions risks wasted design work. Creating a banner at the wrong size means either redoing it or dealing with awkward cropping or stretching once placed.
What a good banner size reference looks like
Covers display, mobile, and social formats together
Since these are genuinely different categories with different standard sizes, a reference spanning all three saves you from checking multiple separate sources.
Is searchable and filterable
Being able to quickly filter to the specific category or platform you need, rather than scrolling a long undifferentiated list, gets you to the right dimension faster.
Stays current with platform changes
Social platform sizes in particular benefit from a reference that’s kept updated as platforms periodically change their requirements.
Common mistakes to avoid
- Designing a banner at a guessed or half-remembered dimension instead of checking the actual current standard size for your specific target.
- Assuming a size that works for one ad network or platform will work identically for another without checking.
- Using an outdated social media image size, especially for platforms that have changed their requirements since you last checked.
- Not accounting for safe margins or text-free zones that some ad formats and platforms specifically require beyond just the raw pixel dimensions.
How to do it with the Web Banner Size Reference
Online Tool Store’s Web Banner Size Reference provides a searchable, filterable reference entirely in your browser.
- Search or filter for the specific ad format, platform, or category you need.
- Find the exact standard pixel dimensions.
- Design your creative to that exact size from the start.
- Reference it again for your next banner or platform-specific graphic.
Because it’s searchable and filterable, finding the exact dimension you need is faster than searching through scattered documentation across different ad networks and platforms.
Frequently asked questions
What are the most common standard display ad sizes?
The leaderboard (728×90), medium rectangle (300×250), and wide skyscraper (160×600) are among the most widely used and recognized standard display ad sizes across many ad networks, though the full standard set includes several additional common formats beyond these three.
Do social media image sizes change often?
They can shift periodically as platforms redesign their interfaces or introduce new ad and content formats — unlike traditional display ad standards, which have remained fairly stable for a long time, social platform requirements are worth double-checking against a currently maintained reference rather than relying on memory.
What happens if I design a banner at the wrong size?
Depending on the specific context, it might be rejected outright by an ad network’s submission requirements, or it might get automatically cropped or stretched to fit the expected slot — neither outcome is ideal, which is why checking the correct dimension before starting design work saves rework.
Final thought
Standard ad and banner sizes exist to make creative interchangeable across ad slots and platforms — designing to the correct dimension from the start avoids the rework of discovering a mismatch after the fact.