Mailchimp Image Sizes: Email Header, Banner, and Footer Dimensions (2026)

Mailchimp email header image size

The 600px everyone quotes is the width of the template shell, not the width of your image — and it is a legacy-builder number. What you actually design against is the content width: 660px in the new builder, 564px for a full-width section in the legacy one. Then you double it, because Mailchimp’s own instruction is to use images with a minimum size of 660px and double your file size to a minimum of 1320px if you want your images to look great on retina displays.

• Check which builder you are in first. Everything on this page forks there. New builder: 660 content, upload 660-1320. Legacy: 564 content, upload 600-1200. Using the legacy figure in the new builder gives you an image Mailchimp has to stretch.
• Constrain the 2x image with the HTML width attribute, not CSS. Mailchimp’s design reference is explicit: doubling an image and then constraining its width with the height and width attributes on the img tag is what keeps it sharp. Outlook on Windows renders through Word, which ignores CSS widths and will display the file at its full 1320px otherwise.
• Subtract your padding. Mailchimp’s own worked example: if 10px of padding is applied around a header image, instead of the header image being 600px wide, you’ll want to make it 580px wide. Do that arithmetic before you export, not after.
• A header is just an image block. There is no separate header asset in Mailchimp with its own spec — which is exactly why no header height exists. Pick a proportion and stay consistent across sends; a 5:1 letterbox (1320 x 264) is a reasonable house style, and it is what the only published email banner dimension anywhere — Substack’s 1100 x 220 — works out to.
• Don’t reuse a landing page hero. The 1500-2500px window is for pages, not email. A 2500px file in a 660px column is several times the 1 MB cap for no visible gain.

Resize a header to 1320px wide → Pick Mailchimp, then Header Banner @2x.

Inline content image sizes by column count

Mailchimp resizes an uploaded image down to fit the content area it lands in, so a file that is too small is the failure mode that shows: it gets stretched, and stretched images are the single most common cause of a blurry Mailchimp email. Match the column count to the minimum above, double it, and the block has enough pixels to work with on every screen.

• Legacy blocks have their own floors. An Image Card with edge-to-edge margins wants 564px, or 528px once margins are on. Image + Text depends on the caption: 352px for a one-third caption, 264px for a half, 176px for two-thirds, 132px for three-quarters.
• Use the responsive blocks, not a text block. Mailchimp’s own troubleshooting advice for a stretched image on mobile is to resize your image, or use one of our mobile-responsive Image, Image Group, Image Card, or Image + Caption content blocks.
• The new builder’s three sizing modes do different things. Original displays the file at its own size up to the content width, Fill stretches it to the full width, and Scale takes it to 10-100% of the original. Only Fill can enlarge a file past its natural size — which is when softness appears.
• Crop before you upload, not in the block. A 3-column grid of images that were each cropped to a different ratio will not line up, whatever the block does. Pick one ratio for the row and cut every image to it.
• Budget the file size per image, not per email. Four images in a 4-column section are four separate 1 MB-capped uploads, and all four load in the same inbox.

Cut an image to a column width → Runs in your browser — no upload, no account.

Mailchimp footer logo size

There is no Mailchimp footer logo spec to look up, because the footer is not a special asset — it is a content section holding your required mailing address and unsubscribe link, plus whatever blocks you add. So the logo follows the same rules as any other image: pick the display width, upload at twice it, stay under 1 MB. The one thing worth being deliberate about is that a footer logo should be visibly smaller than the header one, or the email reads as ending twice.

• Don’t let it go full width. A wordmark stretched across 660px is the most common footer mistake. Set the block to a fixed display width, or drop the logo into one column of a 2-column footer — where the published floor is 330px new builder, 264px legacy.
• PNG with transparency, and check it against dark mode. Some clients invert light backgrounds, and a dark wordmark on a transparent background disappears when they do. A version with a small light-coloured plate behind it survives both.
• A logo is not a photo — export it lossless. JPG artefacts show worst on exactly what a footer logo is made of: hard edges, flat colour, and small type.
• Give it alt text. Many clients block images by default, and a footer logo with no alt text is a blank rectangle above the legally required part of your email.
• Reuse it in the signature, not the other way round. Signature logos are sized for a much narrower box — see email signature image sizes for that spec.

Resize a logo to 600px wide → Pick Mailchimp, then Footer Logo @2x.

Social share image (social card) size

A social card is what renders when someone shares your campaign’s web URL. Mailchimp publishes a floor — at least 600px wide — and no height, deferring to the networks. The practical size is 1200 x 630: that is the 1.91:1 link-preview shape Facebook crops to, and at 1200px it clears Mailchimp’s 600px minimum at 2x. That figure is the web convention, not Mailchimp’s number, and this page marks the difference rather than blurring it.

• 1200 x 630 for Facebook, 1000 x 1500 for Pinterest. One image cannot be both — a 1.91:1 card cropped into a Pinterest feed is a sliver. If Pinterest matters to you, see Pinterest pin sizes and set the card for the network you actually share to.
• Keep text away from the edges. Networks crop link previews differently and none of them tell you where. Anything closer than about 5% to an edge is at risk.
• Set it before you hit send. Social cards can’t be modified once a campaign has gone out, so the proof step is the only chance you get.
• Don’t reuse the header image. A 5:1 letterbox header dropped into a 1.91:1 card slot gets letterboxed or centre-cropped, and the header type usually lands outside the crop.

Resize an image to 1200x630 → Pick Mailchimp, then Social Card (1.91:1).

Landing page hero and background image size

Landing pages are the one place Mailchimp publishes a real dimension range, and it is nothing like the email figures: 1500-2500px wide, because Mailchimp resizes the file down to fit the content area and anything past 2500px may not be resized properly. The squeeze is that the 1 MB cap does not move — so a 2500px hero has to be a well-compressed JPG, not a straight export.

• 2500px is the ceiling, not the target. Go to the top of the range for a full-bleed hero on a wide monitor; 1500px is plenty for a page-width image block and costs a third of the bytes.
• Match the file to your page width. A 780px page needs at least 744px for an image block, a 1332px page needs 1188px. Below that floor the image is being enlarged, which is where softness comes from.
• Backgrounds go in single-column sections. Mailchimp warns that background images in multi-column sections may appear distorted on mobile devices — the section splits into a stack and the image has to cover a shape it was never cropped for.
• Compose for a crop you do not control. A background fills whatever height its section ends up being, and that height changes with the copy. Keep the subject centred and off the edges.
• Height follows the content. Mailchimp’s only guidance is that it depends on the page and that larger images slow the page down — so pick the shortest crop that still works, rather than a tall hero you will scroll past.

Resize a hero to 2500px wide → Pick Mailchimp, then Landing Page Hero.

File size limits and format recommendations

1 MB is the tightest image ceiling among the major email platforms by a wide margin, and it is enforced rather than advised — the upload simply fails. Mailchimp’s own fix when that happens is to use a photo-editing program to resize your image to 1MB or smaller, which in practice means reducing the pixel dimensions first and the JPG quality second.

• JPG for photography, PNG for anything with type. A photo at JPG quality 80 is a fraction of the same image as a PNG; a logo or a screenshot as a JPG picks up visible artefacts around every edge.
• Resize before you compress. A 4000px photo squeezed to 1 MB looks worse than the same photo cut to 1320px and saved at high quality — you are paying for pixels the email will never show.
• GIFs count against the same 1 MB. And Outlook doesn’t animate them — it renders the first frame — so that frame has to stand on its own as a still image.
• Convert CMYK before export. Print files land in email as muddy, shifted colour. Mailchimp is explicit that campaign images need to be RGB.
• Rename the file before uploading. Spaces and special characters break image URLs; dashes or underscores don’t.
• Don’t chase 72 dpi. Pixel dimensions are what an email client renders. The dpi field in your export dialog changes nothing about how the image displays.