Ontools

X (Twitter) Header Size

Short answer: 1500 × 500 px, ratio 3:1, max 5 MB.

safe area 1500 × 3601500 × 500 px
X header: 1500 × 500 pixels (dashed area = visible on every device)

Design at 1500 × 500 — free

Cropping

Depending on the screen, X trims a strip from the top and bottom of the header, and your profile photo covers part of the lower-left corner. Keep text vertically centred and toward the right.

Other X image sizes

Type Size (px)
Header 1500 × 500
Profile photo 400 × 400
Post image (landscape) 1600 × 900
Post image (square) 1080 × 1080