What size should a Shopify banner image be?

Does Shopify publish a banner size in pixels?

As of October 11, 2026, none of the Shopify help and developer pages we read — among them the pages on theme images, Files, the media editor, sections and blocks, and theme settings — gives a pixel size or an aspect ratio for the Image banner, Slideshow or Hero section of Shopify's free themes. Hero is a section in the Horizon themes, per Shopify's changelog.

Shopify's page on theme images says this instead:

In slideshows, image banners and full-width sections, the section sets the shape of the image area, not the image you upload.

For the dimensions that suit your theme, Shopify points to your theme's documentation. Shopify says a paid theme's documentation opens from the theme editor (View documentation); for its free themes, the general documentation is the Themes section of the Help Center, and each theme's Theme Store listing gives its features and version history. We did not read paid themes' documentation or every theme's listing, so check yours.

What size should you start from?

Shopify's blog gives numbers in a general guide to website image sizes rather than a rule for Shopify themes. It suggests 1920px for banners and says banner and background images typically range from 1,920 to 2,560 pixels wide. Its own table gives smaller desktop sizes: a website banner of 1200 x 400 pixels (3:1) and a hero image of 1280 x 720 pixels (16:9). The guide calls these suggested sizes that may need adjusting for a responsive design.

Treat 1920px as a starting width, because the aspect ratio, not the pixel count, decides the crop. Shopify's media editor page says the aspect ratio you crop to controls how much of the image stays visible.

Shopify lists four ways to reduce image cropping:

• Adjust the section settings. In many of Shopify's free themes, Height has an Adapt to first image option that sizes the section to your image instead of cropping it. A slideshow matches its first slide, so a slide with a different aspect ratio is still cropped.
• Set a focal point. The next section covers it.
• Use a source image that fits the image area. For example, a landscape image in a wide section.
• Use a different section or theme.

How does a banner crop on a phone?

On a tall screen, such as a phone or a tablet in portrait, a wide image might be cropped on the left and right. On a wide screen, such as a laptop or desktop monitor, a tall image might be cropped on the top and bottom.

A focal point always displays in frame, even when a theme crops the image to fit the layout. Each image takes one focal point.

Shopify's help page lists the free themes that support focal points: all themes in the Horizon family, and 14 more from a stated version each, such as Dawn 7.0.0 and higher. On a third-party theme, check the theme's documentation for focal point support.

Horizon's release notes, under All versions on its Theme Store listing, say version 3.1.0 introduced "the ability to add mobile-specific media in the Hero section"; the Shopify help pages we read on October 11, 2026 describe no separate mobile image field for an Image banner or Slideshow. If your section's settings show no mobile image field, prepare one image for both crops and set the focal point on the part that must stay in frame.

How large can the banner file be?

On weight, Shopify's two pages agree: 20 MB, stated as a maximum on the Files page and as 20 megabytes on the theme-image page.

On resolution the pages differ, as read on October 11, 2026. The theme-image page limits uploads to 20 megapixels, and its example shrinks a 25-megapixel image to clear an upload error. Yet its quality tips say to upload higher resolution images, up to 25 megapixels, and the Files page gives a maximum of 25 MP.

Keep a banner at 20 megapixels or under and it clears both figures; megapixels are width times height in pixels, divided by one million. If Shopify rejects a file under 20 MB as too large, reduce its pixel dimensions.

Shopify says images don't need to be manually compressed before uploading. Where a customer's browser supports WebP or AVIF, Shopify delivers the image in those formats; whether you can upload an AVIF file yourself is a separate question.

Product images have their own size guidance: see how big a single product image can be.