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Mobile Flex Ad Size 320×320

Validate your 320×320 Mobile Flex Ad for square mobile placements. Verify your 150KB weight limit and dimensions before you go live.

Drag & Drop or Click to Upload your 320 x 320 Image

JPG, PNG, WebP (Max 150KB Limit)

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    The Complete Advertiser’s Guide to the 320×320 Mobile Flex Ad

    What is the 320×320 Mobile Full Page Flex?

    The 320 x 320 Mobile Full Page Flex is a modern square ad unit designed specifically for the mobile web. Unlike thin strips, this format takes up a significant portion of the screen as the user scrolls, offering a “social media” feel similar to an Instagram post.

    It is increasingly favored by advertisers because it offers a large canvas for video, animation, and high-quality product imagery without being as aggressive as a full-screen interstitial.

    Why Use the 320×320 Size?

    • High Visibility: Occupies the center of the mobile screen, commanding attention.
    • Cross-Platform Friendly: Works perfectly on mobile web and often fits within 300×250 ad slots (flex sizing).
    • Rich Media Capable: Large enough to support short video loops or complex animations.

    Technical Specifications

    • Dimensions: 320 pixels wide by 320 pixels tall.
    • File Weight: 150KB – 200KB (depending on network).
    • File Formats: JPG, PNG, GIF, HTML5.

    Best Practices for Design

    Treat this space like a social media post. Use high-quality lifestyle photography or product close-ups. Ensure your logo is visible in the corners and keep your text centered for maximum impact as the user scrolls past.

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