X image sizes: profile, header, and post dimensions

The X image sizes worth memorising are 400 x 400 for your profile photo, 1500 x 500 for your header, and 1200 x 675 for images inside a post. Photos are capped at 5 MB each, profile photos at 2 MB, and X only accepts JPEG, PNG and GIF (X Help Center, September 2026). Everything else on this page is about the parts those three numbers do not tell you: where X crops, which corners of your header are dead space, and why a crisp export can still land blurry.

Most size guides stop at the table. On X (formerly Twitter) the table is the easy half.

#X image sizes at a glance

Those are recommendations, not hard floors. X accepts smaller files and upscales them badly, which is where most "why is my banner fuzzy" complaints come from.

#Profile photo: 400 x 400, cropped to a circle

Upload a square. X displays it as a circle, so the four corners of your image are gone before anyone sees them. Centre the face or the mark, and leave a little breathing room on all sides so the crop does not clip an ear or a letter.

At display size the photo is roughly 133 px on desktop and smaller in the timeline, which has a practical consequence people ignore: fine detail disappears. A wordmark with five words in it becomes grey mush. A single letter, a face, or a high-contrast shape survives.

Animated GIFs are not supported as profile photos. The 2 MB cap is generous for a 400 x 400 JPEG, so there is no reason to compress hard.

#Header photo: 1500 x 500, and the parts nobody sees

This is the size people get wrong, because the safe area is much smaller than the canvas.

Three things sit on top of your header:

• Your profile photo overlaps the lower-left corner, covering roughly a 220 x 220 px circle in header coordinates.
• The Follow or Edit profile button sits over the lower-right on most viewports.
• Mobile trims the top and bottom. Phones render a shorter slice than 3:1, so figure on losing something like 50 px top and bottom.

Design for a safe zone in the upper-centre band, and keep any text there. If your header carries a tagline, put it centre or centre-right and above the vertical midpoint. Test it on a phone before you settle, because the desktop preview flatters you.

One more habit worth copying from accounts that convert: the header is prime real estate for one line about what you do, and the bio underneath is where the link goes. Our guide to adding a link in your X bio covers that half, and the X bio templates post covers the copy.

#In-post images and how X crops them

Here is the rule the design-tool blogs bury. The timeline shows a landscape-shaped preview box. A 16:9 image drops into that box whole. Anything much taller gets centre-cropped for the preview, and only opens at full height when someone taps it.

So the choice is a trade-off, not a best practice:

• 1200 x 675 (16:9) previews uncropped. What you designed is what people scrolling see. Use this whenever the image carries information, such as a chart, a screenshot, a quote card, or a before-and-after.
• 1080 x 1350 (4:5) takes up more vertical space in a mobile feed, which is why it is popular, but you are accepting that the preview shows a centre slice. Use it for photography where a crop still reads, never for text.
• 1080 x 1080 (1:1) sits between the two and is the safest option if the same asset is going to several platforms.

Crop behaviour has shifted more than once across X's web and mobile clients, so treat the preview in the composer as the source of truth for the day you post. If a screenshot has to be legible in the timeline, 16:9 is the only ratio that removes the guesswork.

Text inside images is a separate problem. It has to survive being displayed at around 500 px wide on a phone, so 16 px body text in your design file is unreadable in practice. Set image text at a size that still works when the whole thing is a third of its export width.

#Multi-image posts

Attach up to four images to one post and X tiles them, which changes the geometry completely:

• Two images: side by side, each shown roughly 7:8 (tall and narrow).
• Three images: one large tile on the left, two stacked on the right.
• Four images: a 2 x 2 grid, each tile roughly 2:1 (short and wide).

Design each image for its tile, not for a full-width slot. A four-image grid full of 16:9 exports means every tile gets its top and bottom shaved. This is also the cheapest way to make a thread look considered: one 16:9 hero image on the opening post, then single images on the follow-ups. The structure side of that is in the X thread maker.

#File size, format and quality limits

Photos are capped at 5 MB each. Animated GIFs are capped at 5 MB on mobile and 15 MB on web, and only one GIF is allowed per post. Accepted formats are JPEG, PNG and GIF; BMP, TIFF and the rest are rejected outright (X Help Center, September 2026).

Two practical notes:

• PNG for anything with flat colour or text, JPEG for photographs. A PNG screenshot of a code block or a chart stays crisp where a JPEG version smears the edges.
• sRGB, always. A CMYK export looks washed out and dull once X converts it, and the fix is invisible until you compare side by side.

#Why your images look blurry, and the setting that fixes it

The most common cause is not your export. By default the mobile apps downscale uploads to save data. There is a setting for this: Settings, Accessibility, display and languages, Data usage, where you can set high-quality image uploads to Wi-Fi only or to mobile data and Wi-Fi. Do the same for high-quality image viewing if you want to check your own work honestly.

After that, three things help:

1. Export at 2x and let X downsample. A 2400 x 1350 export that X resizes usually beats a 1200 x 675 export that it re-encodes.
2. Do not upload something already compressed. Screenshots pasted through a chat app arrive pre-mangled.
3. Keep an eye on the 5 MB ceiling. A 4K PNG blows past it fast, and the automatic compression that follows is the ugly kind.

#Link preview cards and ad images

When someone posts a link to your site, the image X pulls comes from your twitter:image or Open Graph tag. Use 1200 x 675 at 16:9 with a summary_large_image card, and keep the file under 5 MB. Get this wrong and your link renders as a small thumbnail next to a line of text, which measurably underperforms the full-width card.

Paid placements follow different specs. X's own creative guidance recommends 1200 x 628 px (1.91:1) or 1200 x 1200 px (1:1) for image ads, and larger uploads are better optimised for the expanded view (X Business, September 2026). If you are working out whether ads belong in your mix at all, what an X ad is covers the formats and the X ads library shows you what competitors are running.

#The 60-second checklist

Before you upload:

• Profile photo square, 400 x 400, readable at thumbnail size.
• Header 1500 x 500, nothing important in the lower-left or far right.
• In-post image 1200 x 675 if it has to read in the timeline.
• sRGB, PNG for text and charts, JPEG for photos, under 5 MB.
• High-quality image uploads turned on in Data usage.

Sizing is the floor, not the ceiling. An image that fits perfectly still competes with everything else in the feed, and the accounts that grow are the ones posting consistently and replying in their niche between posts. If the posting cadence is the part you keep dropping, how to schedule posts on X covers the free and paid routes, and X-Autopilot handles the reply-and-engage layer that a scheduler does not touch.