There is no single Shopify banner size
Shopify does not set one banner size for every store. Each theme decides how hero images, slideshows, and image banners are displayed, and many themes let you choose the section height, such as small, medium, large, or adapt to image. That is why the sizes on this page are practical starting points rather than fixed rules.
For most themes, a hero or image banner between 1920 and 2000 px wide stays sharp on large desktop screens. A 16:9 image (1920 × 1080 px) suits tall hero sections, while a wider 2000 × 800 px image suits slideshows and shorter banners. Announcement or promotional strips are often around 1200 × 400 px.
How themes crop banners on phones
A wide banner shown on a phone is either scaled down until it is very short, or cropped to a taller shape so it still fills the screen. Which one happens depends on the theme and section settings. In both cases, the left and right edges are the parts most likely to disappear, so put products, faces, and text near the centre.
Some themes, including Dawn, let you upload a separate image for mobile. If yours does, export a second, taller version from the same photo, for example a 4:5 or square crop, so the mobile banner is framed on purpose instead of cropped automatically.
Text on banners
Most Shopify themes let you add a heading and button on top of a banner using the theme editor. Using that text instead of writing words into the image keeps them sharp on every screen, makes them readable by search engines and screen readers, and lets you change a sale message without editing the image again.
If you do overlay text in the theme, choose a photo with a calm area of colour where the text will sit, and use the theme's overlay or opacity setting to keep enough contrast.
Keeping banners fast
The banner is usually the largest image on the home page and one of the first things to load, so its file size affects how quickly the page appears. Export photographic banners as JPG at 80–90% quality. A well-prepared 1920 px banner is usually a few hundred kilobytes, which is far lighter than an untouched camera original.