A Twitter/X profile header is 1500×500 pixels at a 3:1 ratio — narrower than a Facebook cover and deeper than a LinkedIn banner, so nothing carries across between them. Like the others, the real constraint is what covers it: your profile picture sits over the lower-left, and on mobile the header crops in from the top and bottom rather than the sides.
Why 1500 × 500?
1500×500 renders sharply across the range of widths X uses for headers without being large enough to trigger heavy compression. The 3:1 ratio is unusual and is the reason a repurposed Facebook cover always looks wrong here — at 2.7:1 it is close enough to seem like it should work, and far enough to visibly crop.
What to Watch Out For
- Your profile photo overlaps the lower-left. Keep that corner clear.
- Mobile crops the top and bottom, not the sides — the opposite of Facebook. Keep content vertically centred.
- Keep the file under 5 MB; X compresses harder above that.
- A 2.7:1 Facebook cover is not close enough to 3:1 to reuse. It will crop visibly.
Resizing Without Uploading
The resizing happens entirely in your browser. Your image is never sent to a server, which matters more than it sounds — most online resizers upload your file to a machine you know nothing about. Here there is nowhere for it to go, so the question does not arise. It also means the tool keeps working with no connection once the page has loaded.
Dimensions verified: 2026-08-05 · Third-party consensus; help.x.com blocks automated access — platform specs change; check against the platform if it matters.